阅读说明：本技术 一种便于维护的浇注对准设备 (Pouring alignment equipment convenient to maintain ) 是由 张家俊 黄荣广 于 2021-08-15 设计创作，主要内容包括：本发明涉及模具设备领域,具体为一种便于维护的浇注对准设备,包括固定底座,所述固定底座的顶端一侧固定安装有支撑架,所述支撑架的外壁一侧设置有调节块,所述调节块的外端一侧设置有固定座,所述固定座的顶端一侧贯穿设置有漏斗,所述漏斗的底端一侧设置有浇注管,且浇注管贯穿固定座的内部一侧,所述支撑架的外壁一侧固定安装有固定板,所述固定板的外壁一侧设置有一组夹臂,所述固定底座的顶端两侧均固定安装有防护板。本发明所述的一种便于维护的浇注对准设备,能够使得整体装置实现更高效便捷的进行浇注对准,有效的提高了使用人员的工作效率,提高整体装置的实用性,带来更好的使用前景。(The invention relates to the field of mold equipment, in particular to pouring alignment equipment convenient to maintain, which comprises a fixed base, wherein a support frame is fixedly installed on one side of the top end of the fixed base, an adjusting block is arranged on one side of the outer wall of the support frame, a fixed seat is arranged on one side of the outer end of the adjusting block, a funnel penetrates through one side of the top end of the fixed seat, a pouring pipe is arranged on one side of the bottom end of the funnel and penetrates through one side of the inner part of the fixed seat, a fixed plate is fixedly installed on one side of the outer wall of the support frame, a group of clamping arms are arranged on one side of the outer wall of the fixed plate, and protection plates are fixedly installed on two sides of the top end of the fixed base. The casting alignment equipment convenient to maintain can enable the integral device to realize efficient and convenient casting alignment, effectively improve the working efficiency of users, improve the practicability of the integral device and bring better use prospect.)

1. The casting alignment equipment convenient to maintain comprises a fixed base (1) and is characterized in that a support frame (2) is fixedly mounted on one side of the top end of the fixed base (1), an adjusting block (3) is arranged on one side of the outer wall of the support frame (2), a fixing seat (4) is arranged on one side of the outer end of the adjusting block (3), a funnel (5) is arranged on one side of the top end of the fixing seat (4) in a penetrating mode, a pouring pipe (6) is arranged on one side of the bottom end of the funnel (5) and penetrates through one side of the inside of the fixing seat (4), a fixing plate (7) is fixedly mounted on one side of the outer wall of the support frame (2), a group of clamping arms (8) are arranged on one side of the outer wall of the fixing plate (7), protection plates (9) are fixedly mounted on two sides of the top end of the fixed base (1), and a group of infrared distance measuring instruments (10) are fixedly mounted on one side of the inner side of the protection plates (9), the equal fixed mounting in outer wall both sides of guard plate (9) has a set of digital display screen (11), and the output of infrared distance meter (10) and the input electric connection of digital display screen (11), top one side fixed mounting of support frame (2) has servo motor (12).

2. The pouring alignment device convenient to maintain as claimed in claim 1, wherein one end of an output shaft of the servo motor (12) is fixedly connected with a lead screw (13), the lead screw (13) and the support frame (2) are arranged in parallel, a thrust bearing (14) is fixedly installed on one side of the outer wall of the support frame (2) corresponding to the lead screw (13), and the support frame (2) is rotatably connected with the lead screw (13) through the thrust bearing (14).

3. The pouring alignment device convenient to maintain is characterized in that a ball nut (15) is installed inside the adjusting block (3) in a matched mode on one side of the lead screw (13), the lead screw (13) is meshed with the ball nut (15), a group of sliding rods (16) are fixedly installed on one side of the outer wall of the supporting frame (2), the sliding rods (16) and the lead screw (13) are arranged in parallel, a sliding sleeve (17) is installed on one side of the sliding rods (16) inside the adjusting block (3) in a matched mode on the inner side of the adjusting block, and the adjusting block (3) is connected with the sliding rods (16) in a sliding mode through the sliding sleeve (17).

4. The pouring alignment equipment convenient for maintenance according to claim 1, wherein a telescopic rod (18) is connected between two of the clamping arms (8), a non-slip mat (19) is fixedly mounted on one side of the outer wall of each clamping arm (8), a set of sliding rails (20) is fixedly mounted on one side of the outer wall of the fixing plate (7) corresponding to the clamping arms (8), a sliding seat is fixedly mounted on one side of the outer end of each clamping arm (8) corresponding to the sliding rail (20), and the clamping arms (8) are slidably connected with the sliding rails (20) through the sliding seats.

5. A pouring alignment device convenient for maintenance according to claim 1, characterized in that a first connecting rod (21) is rotatably connected to one side of the outer end of the clamping arm (8), a second connecting rod (22) is rotatably connected to the other side of the outer end of the clamping arm (8), the first connecting rod (21) and the second connecting rod (22) have the same size structure, a driving rod (23) is rotatably connected to one side of the outer end of the fixing plate (7), and two sides of the outer end of the driving rod (23) are respectively connected to one sides of the outer ends of the first connecting rod (21) and the second connecting rod (22).

6. The pouring alignment equipment convenient to maintain is according to claim 1, characterized in that a placing groove (24) is formed in one side of the inside of the fixing base (1), clamping plates (25) are arranged at two positions of the inner side of the placing groove (24), anti-skidding soft pads are fixedly mounted on one side of the outer wall of each clamping plate (25), pulling rods (26) are fixedly mounted on one side of the outer end of each clamping plate (25), and each pulling rod (26) penetrates through one side of the inside of the fixing base (1).

7. A pouring alignment device convenient for maintenance according to claim 6, wherein a sliding groove (27) is formed in the fixed base (1) corresponding to one side of the pulling rod (26), sliding blocks (28) are fixedly mounted on two sides of the outer surface of the pulling rod (26), and the pulling rod (26) is connected with the sliding groove (27) in a sliding mode through the sliding blocks (28).

8. A pouring alignment device convenient for maintenance according to claim 7, characterized in that the pulling rod (26) is sleeved with a pushing spring (29) on one side of the outer wall, the pushing springs (29) are arranged on one side of the inside of the sliding groove (27), and a pulling button (30) is fixedly arranged on one side of the outer end of the pulling rod (26).

9. The pouring alignment device convenient for maintenance according to claim 1, wherein the pouring tube (6) comprises a first tube body (101), a second tube body (102) and a third tube body (103), the second tube body (102) is arranged on one side of the outer wall of the first tube body (101), the third tube body (103) is arranged on one side of the outer wall of the second tube body (102), a first thread bushing (104) is fixedly arranged on one side of the outer end of the first tube body (101), a first thread groove (105) is etched on one side of the inner wall of the second tube body (102) corresponding to the first thread bushing (104), the first thread bushing (104) and the first thread groove (105) are engaged with each other, a second thread bushing (106) is fixedly arranged on one side of the outer end of the second tube body (102), a second thread groove (107) is etched on one side of the inner portion of the third tube body (103) corresponding to the second thread bushing (106), and the second thread sleeve (106) and the second thread groove (107) are mutually meshed.

Technical Field

The invention relates to the field of mold equipment, in particular to pouring alignment equipment convenient to maintain.

Background

The mold, used in the industrial production to get the various moulds and tools of the desired product by injection molding, blow molding, extrusion, die-casting or forging molding, smelting, stamping, etc., in short, the mold is the tool used for shaping the article, this kind of tool is formed by various parts, different molds are formed by different parts, it mainly realizes the processing of the appearance of the article through the change of the physical state of the shaping material, the prime has the name of "industrial mother", casting is a method of iron product processing; in the early casting, high-temperature liquid molten iron is injected into a mold under normal pressure, and is solidified and molded through polymerization to form a product with the same shape as the inner cavity of the mold.

The existing pouring mold has certain disadvantages when being used, the existing pouring mold is simple in structure, a user needs to finely adjust pouring equipment to pour before use, the position of the mold needs to be calibrated in each pouring process is complex, and the work efficiency of the user is affected, so that the existing pouring mold is inconvenient, and certain influence is brought in the using process. Accordingly, a person skilled in the art provides a casting alignment apparatus that is easy to maintain to solve the problems set forth in the background art described above.

Disclosure of Invention

It is an object of the present invention to provide a casting alignment apparatus that is easy to maintain to solve the problems set forth in the background above.

In order to achieve the purpose, the invention provides the following technical scheme:

a casting alignment device convenient for maintenance comprises a fixed base, a supporting frame is fixedly arranged on one side of the top end of the fixed base, an adjusting block is arranged on one side of the outer wall of the supporting frame, a fixed seat is arranged on one side of the outer end of the adjusting block, a funnel is arranged at one side of the top end of the fixed seat in a penetrating way, a pouring pipe is arranged at one side of the bottom end of the funnel, the pouring tube penetrates through one side of the inner part of the fixed seat, one side of the outer wall of the supporting frame is fixedly provided with a fixed plate, one side of the outer wall of the fixed plate is provided with a group of clamping arms, both sides of the top end of the fixed base are fixedly provided with protective plates, a group of infrared distance measuring instruments are fixedly arranged on one side of the inner side of the protection plate, a group of digital display screens are fixedly arranged on two sides of the outer wall of the protection plate, and the output of infrared distance meter and the input electric connection of digital display screen, the top one side fixed mounting of support frame has servo motor.

As a further scheme of the invention: the servo motor is characterized in that a lead screw is fixedly connected to one end of an output shaft of the servo motor, the lead screw and the support frame are arranged in parallel, a thrust bearing is fixedly mounted on one side, corresponding to the lead screw, of the outer wall of the support frame, and the support frame is rotatably connected with the lead screw through the thrust bearing.

As a still further scheme of the invention: ball nut is installed to the equal gomphosis in one side that the inside of regulating block corresponds the lead screw, and intermeshing between lead screw and the ball nut, outer wall one side fixed mounting of support frame has a set of slide bar, and parallel arrangement each other between slide bar and the lead screw, the slip cap is installed to the equal gomphosis in one side that the inside of regulating block corresponds the slide bar, and the regulating block passes through slip cap and slide bar sliding connection.

As a still further scheme of the invention: be connected with the telescopic link between two arm lock, and the equal fixed mounting in outer wall one side of arm lock has the slipmat, the equal fixed mounting in one side that the outer wall of fixed plate corresponds the arm lock has a set of slip rail, the equal fixed mounting in one side that the outer end of arm lock corresponds the slip rail has the sliding seat, and the arm lock passes through sliding seat and slip rail sliding connection.

As a still further scheme of the invention: the utility model discloses a clamping arm, including the arm lock, the outer end of arm lock is connected with the first connecting rod, the outer end opposite side of arm lock rotates and is connected with the second connecting rod, and the size structure homogeneous phase between first connecting rod and the second connecting rod is the same, the outer end one side of fixed plate rotates and is connected with the actuating lever, and the outer end both sides of actuating lever respectively with first connecting rod and second connecting rod outer end one side and be connected.

As a still further scheme of the invention: the standing groove has been seted up to unable adjustment base's inside one side, the inboard two places of standing groove all are provided with splint, and the equal fixed mounting in outer wall one side of splint has anti-skidding cushion, the equal fixed mounting in outer end one side of splint has the pulling rod, and the pulling rod all runs through unable adjustment base's inside one side.

As a still further scheme of the invention: one side that unable adjustment base's inside corresponds the pulling pole all is provided with the sliding tray, the equal fixed mounting in surface both sides of pulling pole has the sliding block, and the pulling pole passes through sliding block and sliding tray sliding connection.

As a still further scheme of the invention: the pull rod is characterized in that a jacking spring is sleeved on one side of the outer wall of the pull rod, the jacking spring is arranged on one side of the inside of the sliding groove, and pull buttons are fixedly arranged on one sides of the outer ends of the pull rod.

As a still further scheme of the invention: the pouring tube comprises a first tube body, a second tube body and a third tube body, wherein the second tube body is arranged on one side of the outer wall of the first tube body, and the third tube body is arranged on one side of the outer wall of the second tube body.

As a still further scheme of the invention: the outer end one side fixed mounting of first body has first thread bush, the one side sculpture that the inner wall of second body corresponds first thread bush has first thread groove, and intermeshing between first thread bush and the first thread groove, outer end one side fixed mounting of second body has the second thread bush, the inside one side sculpture that corresponds the second thread bush of third body has the second thread groove, and intermeshing between second thread bush and the second thread groove.

Compared with the prior art, the invention has the beneficial effects that:

1. through the arranged fixed base, the fixed base is stably placed, the casting mold is placed in the placing groove arranged on the fixed base, the sliding block in the sliding groove is propped against the pulling rod through the propping spring, the pulling rod can be propped outwards, the clamping plate can be driven to stably fix the casting mold, otherwise, after the pulling rod is pulled outwards, the casting mold can be conveniently detached, the clamping arm is pushed through the telescopic rod, the driving rod is connected with the first connecting rod and the second connecting rod, the clamping and releasing of the clamping arm can be realized, the effect of clamping the casting mold through the clamping arm can be realized, before casting, the infrared distance meter at the position of the protection plate is electrified through the external power supply, the upper end and the lower end of the casting mold are subjected to distance measurement through the infrared distance meter, the numerical value of the digital display screen is in a qualified range, the alignment effect of the mold can be effectively measured, switch on servo motor through external power supply, the lead screw that drives footstep bearing setting through servo motor rotates, cooperation through lead screw and ball nut, it goes up and down to drive the regulating block, cooperation through slide bar and sliding sleeve, it goes up and down to drive the more stable of regulating block, thereby can drive the funnel of fixing base department and go up and down in step, in the pouring hole that the pouring pipe inserted the pouring mould, then can stabilize the pouring through the funnel, when pouring material along with in the mould risees, then can be through the cooperation of lead screw and ball nut, it risees in step to drive the pouring pipe, thereby can effectual pouring mould's pouring effect, effectual improvement user of service's work efficiency, convenient to use personnel use, better for traditional mode.

2. Through the pouring tube that sets up, in order to adjust according to the pouring hole of difference, then can be through the cooperation of first thread bush and first thread groove, then can install the outer wall at first body with the second body, then can stabilize the pouring through the pouring hole aperture of second body, otherwise, through the antiport second body, pull down the second body through the cooperation of first thread bush with first thread groove, then can carry out the supporting pouring hole aperture of first body to first body and stabilize the pouring, with the principle, through the cooperation of second thread bush and second thread groove, then can install the outer wall at the second body with the third body, then can stabilize the pouring hole aperture of third body and pour, the practicality of effectual improvement the device, the user of being convenient for uses, better for traditional mode.

Drawings

FIG. 1 is a schematic view of a casting alignment apparatus for ease of maintenance;

FIG. 2 is a schematic structural view of a support frame in a casting alignment apparatus for easy maintenance;

FIG. 3 is a schematic view of a fixing plate of the casting alignment apparatus for easy maintenance;

FIG. 4 is a schematic structural view of a fixing base in the casting alignment device for easy maintenance;

fig. 5 is a schematic view of a pour tube in a pour alignment apparatus for ease of maintenance.

In the figure: 1. a fixed base; 2. a support frame; 3. an adjusting block; 4. a fixed seat; 5. a funnel; 6. a pouring tube; 7. a fixing plate; 8. clamping arms; 9. a protection plate; 10. an infrared range finder; 11. a digital display screen; 12. a servo motor; 13. a lead screw; 14. a thrust bearing; 15. a ball nut; 16. a slide bar; 17. a sliding sleeve; 18. a telescopic rod; 19. a non-slip mat; 20. a sliding rail; 21. a first connecting rod; 22. a second connecting rod; 23. a drive rod; 24. a placement groove; 25. a splint; 26. pulling a rod; 27. a sliding groove; 28. a slider; 29. pushing the spring; 30. pulling the button; 101. a first pipe body; 102. a second tube body; 103. a third tube; 104. a first threaded sleeve; 105. a first thread groove; 106. a second threaded sleeve; 107. a second thread groove.

Detailed Description

Referring to fig. 1 to 5, in the embodiment of the present invention, a casting alignment apparatus convenient for maintenance includes a fixing base 1, a supporting frame 2 is fixedly installed on one side of the top end of the fixing base 1, an adjusting block 3 is installed on one side of the outer wall of the supporting frame 2, a fixing base 4 is installed on one side of the outer end of the adjusting block 3, a funnel 5 is installed on one side of the top end of the fixing base 4 in a penetrating manner, a casting tube 6 is installed on one side of the bottom end of the funnel 5, the casting tube 6 penetrates one side of the inside of the fixing base 4, a fixing plate 7 is fixedly installed on one side of the outer wall of the supporting frame 2, a set of clamping arms 8 is installed on one side of the outer wall of the fixing plate 7, a protection plate 9 is fixedly installed on both sides of the top end of the fixing base 1, a set of infrared distance meters 10 is fixedly installed on one side of the inside of the protection plate 9, a set of digital display screens 11 is fixedly installed on both sides of the outer walls of the protection plate 9, and the output ends of the infrared distance meters 10 are electrically connected to the input ends of the digital displays 11, a servo motor 12 is fixedly arranged on one side of the top end of the support frame 2.

In FIGS. 1-2: output shaft one end fixedly connected with lead screw 13 of servo motor 12, and mutual parallel arrangement between lead screw 13 and the support frame 2, one side fixed mounting that the outer wall of support frame 2 corresponds lead screw 13 has footstep bearing 14, and support frame 2 rotates with lead screw 13 through footstep bearing 14 to be connected, energize servo motor 12 through the external power supply, lead screw 13 that drives footstep bearing 14 through servo motor 12 and set up rotates, cooperation through lead screw 13 and ball nut 15 drives regulating block 3 and carries out the oscilaltion.

In FIGS. 1-2: ball nut 15 is installed to the inside equal gomphosis in one side that corresponds lead screw 13 of regulating block 3, and intermeshing between lead screw 13 and the ball nut 15, and a set of slide bar 16 of outer wall one side fixed mounting of support frame 2, and parallel arrangement each other between slide bar 16 and the lead screw 13, sliding sleeve 17 is installed to the inside equal gomphosis in one side that corresponds slide bar 16 of regulating block 3, and regulating block 3 passes through sliding sleeve 17 and 16 sliding connection of slide bar.

In fig. 1 and 3: be connected with telescopic link 18 between two arm lock 8, and the equal fixed mounting in outer wall one side of arm lock 8 has slipmat 19, and the equal fixed mounting in one side that the outer wall of fixed plate 7 corresponds arm lock 8 has a set of sliding rail 20, and the equal fixed mounting in one side that the outer end of arm lock 8 corresponds sliding rail 20 has a sliding seat, and arm lock 8 passes through sliding seat and sliding rail 20 sliding connection, and it is tight with the more stable slip clamp of sliding rail 8 that drives through sliding seat and sliding rail 20's cooperation.

In fig. 1 and 3: outer end one side of arm lock 8 rotates and is connected with head rod 21, the outer end opposite side of arm lock 8 rotates and is connected with second connecting rod 22, and big or small structure homogeneous phase between head rod 21 and the second connecting rod 22, outer end one side of fixed plate 7 rotates and is connected with actuating lever 23, and the outer end both sides of actuating lever 23 are connected with outer end one side of head rod 21 and second connecting rod 22 respectively, promote arm lock 8 through telescopic link 18, be connected with head rod 21 and second connecting rod 22 through actuating lever 23, then can realize that arm lock 8 presss from both sides tightly and relaxs, then can press from both sides the effect of tight casting die through arm lock 8.

In fig. 1 and 4: standing groove 24 has been seted up to unable adjustment base 1's inside one side, and standing groove 24's inboard two places all are provided with splint 25, and the equal fixed mounting in outer wall one side of splint 25 has anti-skidding cushion, and the equal fixed mounting in outer end one side of splint 25 has pulling pole 26, and pulling pole 26 all runs through unable adjustment base 1's inside one side, improves the tight effect of splint 25 clamp through anti-skidding cushion.

In fig. 1 and 4: one side that the inside of unable adjustment base 1 corresponds the pulling pole 26 all is provided with sliding tray 27, and the equal fixed mounting in surface both sides of pulling pole 26 has a sliding block 28, and the pulling pole 26 passes through sliding block 28 and sliding tray 27 sliding connection, and through the cooperation of sliding block 28 and sliding tray 27, the more stable slip of pulling pole 26 is moved in the drive.

In fig. 4: all the cover in outer wall one side of pulling pole 26 is equipped with top and moves spring 29, and top and move spring 29 and all set up in inside one side of sliding tray 27, and the equal fixed mounting in outer end one side of pulling pole 26 has the knob 30 that draws, through pinching knob 30, after outwards dragging pulling pole 26, then can be convenient pull down casting die.

In fig. 1 and 5: the pouring pipe 6 comprises a first pipe body 101, a second pipe body 102 and a third pipe body 103, the second pipe body 102 is arranged on one side of the outer wall of the first pipe body 101, the third pipe body 103 is arranged on one side of the outer wall of the second pipe body 102, the second pipe body 102 can be installed on the outer wall of the first pipe body 101 through the matching of a first threaded sleeve 104 and a first threaded groove 105, pouring can be stably conducted on the aperture of a pouring hole of the second pipe body 102, otherwise, the second pipe body 102 is detached through the matching of the first threaded sleeve 104 and the first threaded groove 105, and pouring can be stably conducted on the aperture of the pouring hole matched with the first pipe body 101 through the first pipe body 101.

In fig. 5: a first threaded sleeve 104 is fixedly installed on one side of the outer end of the first pipe body 101, a first threaded groove 105 is etched on one side, corresponding to the first threaded sleeve 104, of the inner wall of the second pipe body 102, a second threaded sleeve 106 is fixedly installed on one side of the outer end of the second pipe body 102, a second threaded groove 107 is etched on one side, corresponding to the second threaded sleeve 106, of the inside of the third pipe body 103, and the second threaded sleeve 106 is engaged with the second threaded groove 107.

The working principle of the invention is as follows: the fixed base 1 is stably placed, a casting mold is placed in a placing groove 24 arranged on the fixed base 1, a sliding block 28 in a sliding groove 27 is propped against a pulling rod 26 through a propping spring 29, the casting mold can be stably fixed by driving a clamping plate 25, otherwise, the casting mold can be conveniently detached after the pulling rod 26 is pulled outwards, the clamping arm 8 is pushed through a telescopic rod 18, the clamping arm 8 can be clamped and loosened through connection of a driving rod 23 and a first connecting rod 21 and a second connecting rod 22, the effect of clamping the casting mold by the clamping arm 8 can be achieved, before casting, the infrared distance measuring instrument 10 at the protection plate 9 is electrified through an external power supply, the upper end and the lower end of the casting mold are separated through the infrared distance measuring instrument 10, when the numerical value of the display screen 11 is within a qualified range, the alignment effect of the casting mold can be effectively measured, the servo motor 12 is electrified through an external power supply, the screw 13 arranged on the thrust bearing 14 is driven to rotate through the servo motor 12, the adjusting block 3 is driven to ascend and descend through the matching of the screw 13 and the ball nut 15, the adjusting block 3 is driven to ascend and descend more stably through the matching of the sliding rod 16 and the sliding sleeve 17, so that the funnel 5 at the fixed seat 4 can be driven to ascend and descend synchronously, when the pouring pipe 6 is inserted into a pouring hole of a pouring mold, stable pouring can be carried out through the funnel 5, when pouring materials in the mold rise, the pouring pipe 6 can be driven to ascend synchronously through the matching of the screw 13 and the ball nut 15, so that the pouring effect of the pouring mold can be effectively improved, the working efficiency of users can be effectively improved, in order to adjust according to different pouring holes, the pouring effects of the first thread bushing 104 and the first thread groove 105 can be matched, then can install second body 102 at the outer wall of first body 101, then can stabilize the pouring gate aperture of second body 102 and pour, otherwise, through reverse rotation second body 102, pull down second body 102 through the cooperation of first thread bush 104 with first thread groove 105, then can stabilize the pouring gate aperture that first body 101 was supporting through first body 101 and pour, with the principle, through the cooperation of second thread bush 106 with second thread groove 107, then can install third body 103 at the outer wall of second body 102, then can stabilize the pouring gate aperture of third body 103 and pour, the practicality of effectual improvement device, it uses to be convenient for the user, it is comparatively practical.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.