CN103860220A - Straight line suturing and incising device for endoscope surgical operation - Google Patents

Straight line suturing and incising device for endoscope surgical operation Download PDF

Info

Publication number
CN103860220A
CN103860220A CN201210595194.5A CN201210595194A CN103860220A CN 103860220 A CN103860220 A CN 103860220A CN 201210595194 A CN201210595194 A CN 201210595194A CN 103860220 A CN103860220 A CN 103860220A
Authority
CN
China
Prior art keywords
nail bin
nail
straight line
boss
insurance institution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201210595194.5A
Other languages
Chinese (zh)
Other versions
CN103860220B (en
Inventor
李文涛
陈望东
舒拓
傅开芬
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suzhou Tianchen International Medical Technology Co Ltd
Original Assignee
Touchstone International Medical Science Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Touchstone International Medical Science Co Ltd filed Critical Touchstone International Medical Science Co Ltd
Priority to CN201210595194.5A priority Critical patent/CN103860220B/en
Publication of CN103860220A publication Critical patent/CN103860220A/en
Application granted granted Critical
Publication of CN103860220B publication Critical patent/CN103860220B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00Surgical instruments, devices or methods, e.g. tourniquets
    • A61B17/068Surgical staplers, e.g. containing multiple staples or clamps
    • A61B17/072Surgical staplers, e.g. containing multiple staples or clamps for applying a row of staples in a single action, e.g. the staples being applied simultaneously
    • A61B17/07207Surgical staplers, e.g. containing multiple staples or clamps for applying a row of staples in a single action, e.g. the staples being applied simultaneously the staples being applied sequentially
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B90/00Instruments, implements or accessories specially adapted for surgery or diagnosis and not covered by any of the groups A61B1/00 - A61B50/00, e.g. for luxation treatment or for protecting wound edges
    • A61B90/08Accessories or related features not otherwise provided for
    • A61B2090/0801Prevention of accidental cutting or pricking
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2560/00Constructional details of operational features of apparatus; Accessories for medical measuring apparatus
    • A61B2560/02Operational features
    • A61B2560/0266Operational features for monitoring or limiting apparatus function
    • A61B2560/028Arrangements to prevent overuse, e.g. by counting the number of uses

Abstract

The invention discloses a straight line suturing and incising device for an endoscope surgical operation. The straight line suturing and incising device for the endoscope surgical operation comprises a body, a nail cabin and a nail anvil, wherein the nail cabin is arranged on a nail cabin frame, the nail anvil is connected with the nail cabin frame in a pivoted mode, and a cutter-pushing holder pushes a cutter and a cocking block to move; a boss is arranged on the end face of the cutter; the nail cabin frame comprises a movable safety mechanism and an inner bottom face; the safety mechanism comprises two states, when the safety mechanism is in a first state, the safety mechanism protrudes out of the inner bottom face, and when the cutter-pushing holder pushes the cutter to move, the safety mechanism is located in the moving direction of the boss of the cutter so that the safety mechanism and the boss interfere mutually; when the safety mechanism is in a second state, the safety mechanism is lower than the bottom face of the boss after the safety mechanism is pressed against by the nail cabin. The straight line suturing and incising device for the endoscope surgical operation has the advantages that the situation that a doctor carries out a next operation under the condition that a fired nail cabin is not replaced is prevented effectively, generation of medical accidents is avoided, and the straight line suturing and incising device is simple in structure and effective.

Description

Straight line seaming and cutting device for the mirror surgical operation of chamber
Technical field
The present invention relates to a kind of surgery instrument, especially a kind of chamber mirror surgical operation straight line seaming and cutting device with secondary fuse mechanism, belongs to technical field of medical instruments.
Background technology
Surgical operation is widely used in wound suture, interior tissue stitching and cutting with straight line seaming and cutting device.Surgical operation is developed so far, and has more and more tended to Minimally Invasive Surgery.Broad sense, the operation that can reduce wound is all called Minimally Invasive Surgery; Narrow sense, Minimally Invasive Surgery refers to the operation of carrying out at Microendoscopic.General of the operation that Microendoscopic carries out need to be opened several apertures on patient's health, and excision, suture tissue and auxiliary apparatus are stretched in patient body and performed the operation from aperture.The wound that Minimally Invasive Surgery brings to patient is little, and patient can recover in a short period of time, and therefore Minimally Invasive Surgery is more and more subject to people's attention.
US Patent No. 7753246 has disclosed a kind of chamber mirror surgical operation straight line seaming and cutting device for Minimally Invasive Surgery, comprise an instrument body, described instrument body comprises that housing and a pivot be located at the percussion handle on housing, in this housing, be provided with a relatively-movable percussion push rod, described percussion push rod can promote to be positioned at the nail-head component of housing front end and sew up and excise.Concrete, described nail-head component comprises a nail bin frame, and one and the pivotally connected nail anvil of nail bin frame.On described nail bin frame, be removably provided with nail bin, nail bin be provided with in one group, be provided with pushing slice of nail, anastomosis staple put nail hole, what be generally 4 rows or 6 rows puts nail hole.Described nail anvil is being provided with nail forming tank with described putting on relative position, nail hole.Described nail-head component also comprise in an adapter that is arranged on movably nail-head component, with the push broach bar that percussion push rod connects, the far-end of described push broach bar is fixed an I shape cutting knife, this I shape cutting knife in the process of advancing by nail bin and nail anvil closure.The distal center of described cutting knife is provided with blade, and it cuts off the tissue being positioned between nail bin and nail anvil in the process of advancing.The blade both sides of described I shape cutting knife are provided with percussion piece, and in the process of advancing at I shape cutting knife, I shape cutter driving percussion piece is pushed out of pushing slice of nail outside nail bin successively, and then pushing slice of nail is pushed out of anastomosis staple outside nail bin and orders and close organizationally.In prior art, doctor completes after above-mentioned seaming and cutting action, first needs apparatus to reset, and then changes nail bin, so that surgical operation carries out seaming and cutting operation next time with straight line seaming and cutting device.
But due to some careless doctors or the doctor that lacks experience, can in the case of do not change the nail bin of having pulled the trigger, carry out on seaming and cutting operation once, can cause like this generation of malpractice, carried out excision and but do not sewed up.In order to prevent the generation of this type of accident, prior art has proposed the theory of the anti-secondary percussion of secondary fuse,, in the case of not changing the nail bin of having pulled the trigger, pulls the trigger handle and can not be pressed.Like this, fundamentally prevent the malpractice producing due to doctor's maloperation.
US Patent No. 5485947 discloses Liao Liangzhong secondary fuse mechanism.In the first mechanism, nail bin is provided with a chute, is provided with slidably a flexure strip in this chute.When original state, it is outer and by upwards jack-up of push broach bar that this flexure strip stretches out in described chute, and the projection being now positioned on breach and the nail bin of push broach bar near-end is separated from each other, and guarantees that described push broach bar can be pushed.In the time that push broach bar moves to far-end, described push broach bar is pushed into flexure strip in described chute, and the height of this push broach bar declines.After described push broach bar is resetted, described projection is just stuck in the breach of push broach bar, and this push broach bar cannot be moved again, has played the effect of secondary fuse.The principle of the second mechanism and the first mechanism are similar, and a pivot member is replaced to flexure strip.When original state, pivot member is lifted push broach bar, makes the breach on push broach bar avoid the projection on nail bin.After described push broach bar is resetted, pivot member upset, declines the height of push broach bar, and described projection is just stuck in the breach of push broach bar, and described push broach bar cannot be moved again, has played the effect of secondary fuse.
In prior art, because the parts that relate to are very little, and be all assemblied in nail bin, cause surgical operation straight line seaming and cutting device to be produced and assembling difficulty.
Summary of the invention
Object of the present invention: the chamber mirror surgical operation straight line seaming and cutting device that proposes a kind of secondary fuse mechanism with simple structure.
Object of the present invention, will be achieved by the following technical programs:
Straight line seaming and cutting device for the mirror surgical operation of a kind of chamber, comprising: a body; One is arranged at the nail bin frame of described body distal end; On described nail bin frame, be removably provided with nail bin, described nail bin be provided with in several, be provided with pushing slice of nail, anastomosis staple put nail hole, be arranged in the chute of described nail bin for promoting the percussion piece of described pushing slice of nail; One nail anvil pivotally connected with described nail bin frame; One for connecting the adapter of described body and nail bin frame, is provided with movably a push broach bar and is placed in the cutting knife of described push broach bar far-end in described adapter, and described push broach bar promotes described percussion piece and moves; The end face of described cutting knife is provided with boss, and this boss has bottom surface; Described nail bin frame comprises insurance institution and an inner bottom surface; Described insurance institution comprises two states, when the first state, described insurance institution protrudes from described inner bottom surface, in the time that described push broach bar promotes described cutting knife and moves, described insurance institution is positioned on the moving direction of boss of described cutting knife, makes described insurance institution and described boss interference; When the second state, described insurance institution is subject to the bottom surface lower than boss after compressing of nail bin.
Preferably, when the second state, described insurance institution is depressed in described nail bin frame and lower than inner bottom surface.
Preferably, described insurance institution comprises shell fragment and insurance block, and one end of described shell fragment is fixed on described nail bin frame, the fixing insurance of other end block.
Preferably, the inner bottom surface of described nail bin frame has a bit-avoiding slot, and when described insurance institution is during in the second state, described insurance block is accommodated in described bit-avoiding slot.
Preferably, the trigger mechanism of described insurance institution is the bottom surface of described percussion piece.
Beneficial effect of the present invention is mainly reflected in: effectively prevent doctor in the case of do not change the nail bin of having pulled the trigger, carry out on operation once, avoid the generation of malpractice, simple in structure effectively.
Brief description of the drawings
Fig. 1 is the schematic diagram that is located at the nail bin frame in adapter of the preferred embodiment of the present invention.
Fig. 2 is the cutaway view along A-A in Fig. 1.
Fig. 3 is the cutaway view along B-B in Fig. 1.
Fig. 4 is the enlarged drawing of A part in Fig. 3.
Fig. 5 is the front view of the nail-head component of the preferred embodiment of the present invention, and nail bin is not now installed, first insurance.
Fig. 6 is the front view of the nail-head component of the preferred embodiment of the present invention, nail bin is now installed, arming.
Wherein: 1, nail bin frame; 11, bit-avoiding slot; 12, shell fragment; 13, insurance block; 14, inner bottom surface; 2, nail anvil; 3, nail bin; 4, take over; 5, percussion piece; 6, push broach bar; 7, cutting knife; 71, boss; 72, bottom surface.
Detailed description of the invention
The present invention has disclosed a kind of chamber mirror surgical operation straight line seaming and cutting device for Minimally Invasive Surgery, as shown in Figure 1 to Figure 3, consistent with prior art, comprising: a housing, is positioned at the adapter 4 of housing far-end.The far-end of described adapter 4 is nail-head component, comprising: a nail bin frame 1 and one and the pivotally connected nail anvil 2 of described nail bin frame 1.On described nail bin frame 1, be removably provided with nail bin 3, described nail bin 3 be provided with in one group, be provided with pushing slice of nail, anastomosis staple put nail hole; Be arranged in the chute of described nail bin 3 for the percussion piece 5 that promotes described pushing slice of nail.
In described adapter 4, be provided with movably a push broach bar 6; The far-end of described push broach bar 6 is fixed a cutting knife 7, on described cutting knife 7, has projection, is I shape, described I shape cutting knife 7 in the process of advancing first compressing tissue make to expand organize attenuation and evenly, thereby further by nail bin 3 and nail anvil 2 closures; The distal center of described I shape cutting knife 7 is provided with blade, described push broach bar 6 promotes cutting knife 7 this blade in the process of advancing the tissue being positioned between nail bin 3 and nail anvil 2 is cut off, and described push broach bar 6 promotes described percussion piece 5 pushing slice of nail is pushed out of outside nail bin 3 successively in the process of advancing, and then pushing slice of nail is pushed out of anastomosis staple outside nail bin 3 and orders and close organizationally.
Specifically as shown in Figure 4, feature of the present invention is: the end face of described cutting knife 7 is provided with a boss 71, and this boss 71 has bottom surface 72; Described nail bin frame 1 comprises an insurance institution and an inner bottom surface 14; Described insurance institution comprises shell fragment 12 and insurance block 13, and one end of described shell fragment 12 is welded or connected and fixed on described nail bin frame 1, the fixing insurance of other end block 13.
Simply introduce some work process of the present invention below.
As shown in Figure 5, in the time that the nail-head component of the preferred embodiment of the present invention is not installed nail bin 3, described insurance institution protrudes from described inner bottom surface 14, and in the time that described push broach bar 6 promotes described cutting knife 7 and moves, described insurance institution is kept out by described boss 71; Be that described insurance institution is arranged in the advance route of cutting knife 7, described cutting knife 7 can not be moved to far-end along straight line, and then push broach bar 6 can not be moved, both interfere mutually.Like this, the preferred embodiment of the present invention is in a safety position.
As shown in Figure 6, the trigger mechanism of described insurance institution is the bottom surface of described percussion piece 5.When loading onto after nail bin 3, the bottom surface of described percussion piece 5 presses down described insurance institution, described insurance institution is depressed in described nail bin frame 1 and lower than the bottom surface 72 of boss 71.In this preferred embodiment, the inner bottom surface 14 of described nail bin frame 1 has a bit-avoiding slot 11, and in the time that the bottom surface of described percussion piece 5 presses down described insurance institution, described insurance block 13 is accommodated in described bit-avoiding slot 11 and lower than the bottom surface 72 of boss 71.In this preferred embodiment, shell fragment 12 now and insurance block 13 are all lower than the inner bottom surface of nail bin frame 1, and Ji Gai insurance institution is contained in bit-avoiding slot 11 completely.Like this, described insurance institution cannot keep out described boss 71 and advances; Be the boss 71 that described insurance institution has avoided cutting knife 7, and then make push broach bar 6 can promote cutting knife 7 to move.At this moment can pull the trigger this straight line seaming and cutting device.
It should be noted that, after preferred embodiment of the present invention percussion, described percussion piece 5 can be positioned at the far-end of described nail bin 3 and can not reset, insurance institution has just lost trigger mechanism like this, can return to the first state in Fig. 5, be that described insurance institution keeps out described boss 71 again, played the effect of secondary fuse.Only have the nail bin of replacing could remove this secondary fuse, prevent from again pulling the trigger in the situation that not changing nail bin.
In the present invention, the word of described expression position and direction, is all using exercises on apparatus author as reference, is near-end near one end of operator, is far-end away from one end of operator.
The present invention still has numerous embodiments, and all employing equivalents or equivalent transformation and all technical schemes of forming, within all dropping on protection scope of the present invention.

Claims (5)

1. a straight line seaming and cutting device for chamber mirror surgical operation, comprising:
One body;
One is arranged at the nail bin frame (1) of described body distal end; On described nail bin frame (1), be removably provided with nail bin (3), described nail bin (3) be provided with in several, be provided with pushing slice of nail, anastomosis staple put nail hole, be arranged in the chute of described nail bin (3) for the percussion piece (5) that promotes described pushing slice of nail;
One nail anvil (2) pivotally connected with described nail bin frame (1);
One for connecting the adapter (4) of described body and nail bin frame, in described adapter (4), be provided with movably a push broach bar (6) and be placed in the cutting knife (7) of described push broach bar (6) far-end, it is mobile that described push broach bar (6) promotes described percussion piece (5);
It is characterized in that: the end face of described cutting knife (7) is provided with boss (71), this boss (71) has bottom surface (72);
Described nail bin frame (1) comprises insurance institution and an inner bottom surface (14);
Described insurance institution comprises two states,
When the first state, described insurance institution protrudes from described inner bottom surface (14), in the time that described push broach bar (6) promotes described cutting knife (7) movement, described insurance institution is positioned on the moving direction of boss (71) of described cutting knife (7), makes described insurance institution and described boss (71) interference;
When the second state, described insurance institution is subject to the bottom surface (72) lower than boss (71) after compressing of nail bin (3).
2. straight line seaming and cutting device for the mirror surgical operation of chamber according to claim 1, is characterized in that: when the second state, described insurance institution is depressed in described nail bin frame (1) and lower than inner bottom surface (14).
3. straight line seaming and cutting device for the mirror surgical operation of chamber according to claim 1, it is characterized in that: described insurance institution comprises shell fragment (12) and insurance block (13), it is upper that described nail bin frame (1) is fixed in one end of described shell fragment (12), the other end fixing insurance block (13).
4. straight line seaming and cutting device for the mirror surgical operation of chamber according to claim 3, it is characterized in that: the inner bottom surface (14) of described nail bin frame (1) has a bit-avoiding slot (11), when described insurance institution is during in the second state, described insurance block (13) is accommodated in described bit-avoiding slot (11).
5. the straight line seaming and cutting device for the chamber mirror surgical operation described in any according to claim 1 to 4, is characterized in that: the trigger mechanism of described insurance institution is the bottom surface of described percussion piece (5).
CN201210595194.5A 2012-12-18 2012-12-18 Chamber mirror surgical operation straight line seaming and cutting device Active CN103860220B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201210595194.5A CN103860220B (en) 2012-12-18 2012-12-18 Chamber mirror surgical operation straight line seaming and cutting device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201210595194.5A CN103860220B (en) 2012-12-18 2012-12-18 Chamber mirror surgical operation straight line seaming and cutting device

Publications (2)

Publication Number Publication Date
CN103860220A true CN103860220A (en) 2014-06-18
CN103860220B CN103860220B (en) 2016-02-10

Family

ID=50899640

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201210595194.5A Active CN103860220B (en) 2012-12-18 2012-12-18 Chamber mirror surgical operation straight line seaming and cutting device

Country Status (1)

Country Link
CN (1) CN103860220B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107890362A (en) * 2017-02-28 2018-04-10 江苏风和医疗器材股份有限公司 Surgical instruments
WO2019114495A1 (en) * 2017-12-14 2019-06-20 苏州天臣国际医疗科技有限公司 Staple cartridge assembly and medical stapler using same

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5307976A (en) * 1991-10-18 1994-05-03 Ethicon, Inc. Linear stapling mechanism with cutting means
CN2868207Y (en) * 2005-12-14 2007-02-14 苏州天臣国际医疗科技有限公司 Tubular binding instrument having secondary firing-proof mechanism
US20080179375A1 (en) * 2007-01-31 2008-07-31 Tyco Healthcare Group Lp Surgical instrument with replaceable loading unit
CN101797173A (en) * 2010-03-02 2010-08-11 瑞奇外科器械(北京)有限公司 Skidproof nail box of surgical linear cutting stapler
CN203074787U (en) * 2012-12-18 2013-07-24 苏州天臣国际医疗科技有限公司 Straight line suturing and incising device for endoscope surgical operation

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5307976A (en) * 1991-10-18 1994-05-03 Ethicon, Inc. Linear stapling mechanism with cutting means
CN2868207Y (en) * 2005-12-14 2007-02-14 苏州天臣国际医疗科技有限公司 Tubular binding instrument having secondary firing-proof mechanism
US20080179375A1 (en) * 2007-01-31 2008-07-31 Tyco Healthcare Group Lp Surgical instrument with replaceable loading unit
CN101797173A (en) * 2010-03-02 2010-08-11 瑞奇外科器械(北京)有限公司 Skidproof nail box of surgical linear cutting stapler
CN203074787U (en) * 2012-12-18 2013-07-24 苏州天臣国际医疗科技有限公司 Straight line suturing and incising device for endoscope surgical operation

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107890362A (en) * 2017-02-28 2018-04-10 江苏风和医疗器材股份有限公司 Surgical instruments
WO2019114495A1 (en) * 2017-12-14 2019-06-20 苏州天臣国际医疗科技有限公司 Staple cartridge assembly and medical stapler using same
AU2018382026B2 (en) * 2017-12-14 2020-12-24 Touchstone International Medical Science Co., Ltd. Staple cartridge assembly and medical stapler using the staple cartridge assembly
JP2021506417A (en) * 2017-12-14 2021-02-22 タッチストーン インターナショナル メディカル サイエンス カンパニーリミテッドTouchstone International Medical Science Co., Ltd. Staple cartridge assembly and medical stapler using it
JP7049003B2 (en) 2017-12-14 2022-04-06 タッチストーン インターナショナル メディカル サイエンス カンパニーリミテッド Staple cartridge assembly and medical stapler using it
US11337695B2 (en) 2017-12-14 2022-05-24 Touchstone International Medical Science Co., Ltd. Staple cartridge assembly and medical stapler using the staple cartridge assembly

Also Published As

Publication number Publication date
CN103860220B (en) 2016-02-10

Similar Documents

Publication Publication Date Title
CN103860225B (en) Linear seam cutting device
CN103860221B (en) Linear stapling cutter nail-head component
CN103860222A (en) Linear suturing/cutting device
CN202982103U (en) Straight-line sewing and cutting device
JP3213928U (en) Stapling head assembly and endoscopic surgical suture cutting device
CN204364049U (en) A kind of nail-head component and chamber mirror surgical operation seaming and cutting device
CN102579096B (en) Linear cutting element with E-shaped guiding element
CN103860223B (en) The nail-head component of Linear stapling cutter
CN103860226B (en) Linear stapling cutter and anti-secondary firing lock thereof
CN105796143A (en) Nail head component and endoscopic surgery suturing and cutting device
CN204364052U (en) A kind of nail-head component and there is the chamber mirror Endo-GIA of this nail-head component
CN103860220B (en) Chamber mirror surgical operation straight line seaming and cutting device
CN203074789U (en) Nail head assembly of linear stitching and cutting machine
CN203609466U (en) Linear stitching and cutting apparatus
CN202982104U (en) Straight stitching and cutting device
CN103860224B (en) Straight line stitching instrument cutter sweep
CN202982105U (en) Nail head assembly of straight stitching and cutting device
CN203074787U (en) Straight line suturing and incising device for endoscope surgical operation
CN202051756U (en) Linear cutting and suturing machine
CN105796146B (en) A kind of nail-head component and the hysteroscope Endo-GIA with the nail-head component
CN204364051U (en) A kind of nail-head component and chamber mirror surgical operation seaming and cutting device
CN202526260U (en) Linear incision component with E-shaped guiding element
CN203074788U (en) Linear type stitching and cutting machine
CN202982102U (en) Straight stitching and cutting device and second percussion prevention mechanism thereof
CN100589766C (en) Cutting mechanism for arc cutting stitching instrument

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CP03 Change of name, title or address
CP03 Change of name, title or address

Address after: 215021 No. 278 Dongping Street, Suzhou Industrial Park, Jiangsu Province

Patentee after: Tianchen International Medical Technology Co., Ltd

Address before: 215021, 1355 international science and Technology Park, Jinji Lake Avenue, Suzhou Industrial Park, Jiangsu, 3 21A

Patentee before: TOUCHSTONE INTERNATIONAL MEDICAL SCIENCE Co.,Ltd.