A utility knife

Abstract

The present invention relates to a utility knife, comprising a housing, a knife holder, a blade, a gear operating member, and a safety operating member. The housing has a positioning direction that is at an angle to the sliding direction of the gear operating member. In this positioning direction, the first gear is farther away from the positioning portion of the gear operating member than the remaining areas on the sliding track except the first gear. In this way, the gear operating member, in addition to being used for gear switching, can also resist and cooperate with the knife holder, thereby affecting whether the knife holder can slide forward independently, without the need to set a pin shaft, a pin hole, a retreat portion, a support surface, an elastic element set on the lock pin to apply elastic force to the support surface and the retreat portion, etc., and without the need to set an elastic locking piece, a locking tongue, a support surface and a retreat portion, etc., so that the utility knife of the present invention has fewer parts, so that the material cost is lower, the assembly process is less, the assembly is more convenient and time-saving, and the parts are not easily lost.

Description

Technical Field

[0001] The invention relates to the field of hand tools, in particular to a utility knife. Background Art

[0002] A utility knife is a commonly used hand tool used for cutting paper, leather, plastic sheets, cardboard, etc. The utility knife generally comprises a housing, a knife holder and a blade. The housing has a receiving cavity and a front opening connected to the receiving cavity. The knife holder is slidably arranged in the receiving cavity of the housing. The blade is arranged on the knife holder and can move in and out of the front opening as the knife holder slides.

[0003] In order to overcome the problem that the blade does not automatically retract after being extended, there are existing solutions that have made improvements. For example, the Chinese invention patent with application number CN201110364694.3 (authorization announcement number CN102398272B) discloses a "gear safety knife", which includes an outer frame, a knife holder, a blade, a push button, a gear and a gear slider, etc. The gear slider is provided with a control member that is exposed from the slide groove and can be positioned in the gear position, an interlocking structure is provided between the gear slider and the knife holder, and a reset elastic member that applies elastic force to the knife holder into the outer frame is connected to the knife holder, when the gear slider is positioned in the gear position of extending the blade out of the outer frame through the control member, the interlocking structure locks the knife holder and the gear slider together, and when the gear slider is positioned in the gear position of retracting the blade into the outer frame through the control member, the interlocking structure unlocks the knife holder and the gear slider; the knife holder and the gear slider have an overlapping portion in the front-to-back direction. The interlocking structure includes a lock pin, a pin hole, a supporting surface and a retreating portion. When the shift slider is positioned at a shift position where the blade is extended out of the outer frame, the lock pin is supported by the supporting surface and extends into the pin hole to lock the tool holder and the shift slider together. When the shift slider is positioned at a shift position where the blade is retracted into the outer frame, the lock pin retreats into the retreating portion and escapes from the pin hole to unlock the tool holder and the shift slider. Alternatively, the interlocking structure includes an elastic locking piece, a supporting surface and a retreating portion. The elastic locking piece is arranged on the shift slider. A lock hole and a lock tongue are arranged on the elastic locking piece and the tool holder. The supporting surface and the retreating portion are adjacently arranged on the outer frame. When the shift slider (through the operating member) is positioned at a shift position where the blade is extended out of the outer frame, the elastic locking piece is supported by the supporting surface so that the lock hole is sleeved on the lock tongue to lock the tool holder and the shift slider together. When the shift slider (through the operating member) is positioned at a shift position where the blade is retracted into the outer frame, the elastic locking piece retreats into the retreating portion so that the lock hole is removed from the lock tongue to unlock the tool holder and the shift slider. It can be seen that the gear safety knife has two usage modes: gear and safety. In the safety mode, the blade can automatically retract into the outer frame.

[0004] However, the above patents have the following problems: first, the interlocking structure includes a pin shaft, a pin hole, a retreat portion, a support surface, an elastic element provided on the lock pin to apply elastic force to the support surface and the retreat portion, etc., or the interlocking structure includes an elastic locking piece, a lock tongue, a support surface and a retreat portion. It can be seen that the utility knife has many parts, so the material cost is high, and the assembly process is more and more time-consuming;

[0005] Second, the pin and the pin hole or the lock plate and the lock tongue have relatively small sizes, so the assembly accuracy is high. If the position is slightly deviated, the pin and the pin hole, or the lock plate and the lock tongue cannot interlock well, thus making the interlocking structure invalid. In addition, the pin and the lock tongue of the interlocking structure are small in size and easy to lose.

[0006] Third, after the external force begins to act on the operating member (equivalent to the gear operating member mentioned below), that is, when the operating member is just pressed into the shell but not pushed to slide forward, the tool holder and the gear slider cannot be interlocked immediately because the locking pin has not extended into the pin hole. At this time, if the utility knife is not used normally or violently, the tool holder can still slide forward independently, so the blade on the tool holder will be thrown out and there is a risk of hurting the user himself or others; in particular, if the retreat portion includes an inclined surface transitioning to the supporting surface, then, in addition to the blade being thrown out when the operating member is pressed into the shell, when the operating member is at the corresponding position of the retreat portion (the operating member may have slid a distance at this time), including at the corresponding position of the inclined surface of the retreat portion, the tool holder and the gear slider are not interlocked, and the blade will also be thrown out, posing a safety hazard.

[0007] Therefore, the utility knife still needs to be improved. Summary of the invention

[0008] The first technical problem to be solved by the present invention is to provide a utility knife with fewer parts and more convenient assembly in view of the above-mentioned prior art.

[0009] The second technical problem to be solved by the present invention is to provide a utility knife with which the gear control member can immediately prevent the tool holder from sliding forward independently after the external force starts to act on the gear control member.

[0010] The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: a utility knife, comprising

[0011] The housing has a receiving cavity, a front opening communicating with the receiving cavity, and a sliding track disposed in the receiving cavity for sliding the gear position operating member described below, wherein the sliding track has gear positions, and the gear positions include a first gear position and at least one second gear position disposed on the sliding track at intervals along the sliding direction of the gear position operating member described below;

[0012] A tool holder is slidably disposed in the housing cavity of the shell;

[0013] A blade, which is arranged on the blade holder and can move in and out of the front opening as the blade holder slides;

[0014] The gear position control member has a positioning portion that is positioned and matched with the first gear position and each second gear position. Under the action of external force, the gear position control member can slide forward and backward relative to the housing and can make the positioning portion be located in different gear positions, so that the blade can enter and exit the front opening of the housing and can realize the positioning of the blade extending out of the housing;

[0015] A safety control member is arranged on the knife holder, and is used to drive the knife holder to slide forward and backward, thereby driving the blade to move forward and backward in and out of the front opening;

[0016] Features:

[0017] The housing has a positioning direction which is at an angle to the sliding direction of the gear operating member, and in this positioning direction, compared with the remaining areas on the sliding track except the first gear, the first gear is farther away from the positioning portion of the gear operating member;

[0018] When the positioning portion of the gear operating member is located in the first gear position, the gear operating member does not interfere with the tool holder, and the tool holder slides forward through the safety operating member;

[0019] When the positioning portion of the gear control member is located at a position other than the first gear position, the gear control member can resist and cooperate with the tool holder, and the tool holder can slide forward through the gear control member.

[0020] The structures of the first gear position, the second gear position and the positioning portion can be various. Preferably, the first gear position is a first groove formed by the sliding track being recessed in the positioning direction to accommodate the positioning portion, and the second gear position is a second groove formed by the sliding track being recessed in the positioning direction to accommodate the positioning portion. In the positioning direction, the groove depth of the first groove is greater than the groove depth of each second groove, so that in the positioning direction, compared with the remaining area on the sliding track except the first groove, the groove bottom of the first groove is farther away from the positioning portion of the gear control member;

[0021] The positioning portion is a positioning protrusion.

[0022] By providing the positioning protrusion, the first groove and the second groove, the structure is reasonable and simple, the stability is good and it is not easy to fail.

[0023] Preferably, the tool holder has an interference matching direction which is at an angle to the advancing direction of the tool holder;

[0024] The tool holder has a first limiting portion and a second limiting portion, the first limiting portion extends in the direction of the interference fit, and the second limiting portion is located at the rear side of the first limiting portion and extends in the direction of the interference fit;

[0025] The gear position control member has a transmission part, and the positioning part is located at the rear side of the transmission part and at the front side of the second limiting part;

[0026] When the positioning portion of the gear control member is located in the first gear position, the transmission portion does not interfere with the first limiting portion, and the positioning portion and the second limiting portion do not overlap each other in the forward direction, and the sliding safety control member can drive the knife holder to slide forward and backward, thereby driving the blade to enter and exit the front opening;

[0027] Except when the positioning portion of the gear operating member is located in the first gear, the transmission portion and the first limiting portion at least partially overlap with each other in the forward direction, and the positioning portion and the second limiting portion at least partially overlap with each other in the forward direction. Sliding the gear operating member forward can make its transmission portion move forward and come into contact with the first limiting portion, thereby driving the tool holder to move forward and preventing the tool holder from resetting backward on its own.

[0028] Such a design enables the positioning portion of the gear control member to not only cooperate with the gear positioning to position the extent to which the blade extends out of the shell, but also to cooperate with the second limiting portion, and together with the transmission portion, enable the gear control member to act on the tool holder, so that the safety control member cannot independently drive the tool holder to slide forward and cannot enable the blade to independently enter and exit the front opening. In other words, the positioning portion has two functions. Compared with a solution in which the positioning portion is only used to position the extent to which the blade extends out of the shell, this solution has fewer components and a more compact structure. In addition, when acting on the gear control member to switch gears, the gear control member can simultaneously act on the tool holder to affect whether the tool holder can slide forward under the action of the safety control member. When the user uses it, the movement is smoother and the operation is more convenient.

[0029] To further solve the second technical problem of the present invention: when the positioning portion of the gear control member is located in the first gear, the positioning portion and the second limiting portion are close to each other in the interference matching direction and the distance between them is small.

[0030] In this way, when external force begins to act on the gear control member, the positioning portion originally located in the first gear moves toward the tool holder in the direction of interference and cooperation. Because the spacing is small, the positioning portion can immediately begin to overlap with the second limiting portion in the front and rear directions, that is, the gear control member can immediately interfere with the tool holder. At this time, if the utility knife is used abnormally or violently, the blade will not be thrown out and safety is higher.

[0031] In order to enable the gear control member to immediately drive the blade to extend and retract when sliding in the front-back direction, when the positioning portion is in the first gear position, the transmission portion and the first limiting portion are partially overlapped in the forward direction, and at this time, the distance between the transmission portion and the first limiting portion in the forward direction of the knife holder is small;

[0032] or / and, when the positioning portion and the second limiting portion at least partially overlap each other in the advancing direction, the positioning portion and the second limiting portion are close to each other in the advancing direction of the tool holder and the distance between them is small;

[0033] Or / and, the back side of the tool holder has a limit groove, a limit column and a third spring mounted outside the limit column are arranged between the limit groove and the inner wall of the shell, the head of the limit column is adapted to the limit groove, one end of the third spring is against the limit column and the other end is against the inner wall of the shell, and the third spring has a tendency to support the limit column so that the head of the limit column is stuck in the limit groove.

[0034] Because the front-to-back spacing between the transmission part and the first limiting part is small, when the gear control member slides forward, it can immediately act on the first limiting part through the transmission part to drive the blade to extend out of the front opening. In addition, when the positioning part is in the first gear, the transmission part and the first limiting part have partially overlapped in the forward direction, so that the operation feel is better, there will be no jamming, and the operation is smoother.

[0035] Or / and, when the gear control member slides backward, the positioning portion can immediately act on the second limiting portion to drive the blade to gradually retract into the housing; in this way, the forward and backward sliding of the gear control member can be immediately reflected as the extension and retraction of the blade, with almost no delay, so that the extension and retraction reaction of the blade is relatively sensitive;

[0036] Or / and, by setting a limit column, there is a limiting effect on the tool holder. When the positioning portion is in the first gear, if the utility knife is used abnormally or violently, the tool holder is not likely to move forward independently due to the limitation of the tool holder by the limit column, so that the blade is not likely to be thrown out and injure the user himself or others.

[0037] In order to increase friction and even force, at least one of the transmission part and the first limiting part is a first plane at a position where the two parts abut against each other;

[0038] Or / and, at least one of the positioning portion and the second limiting portion is a second plane at a position where the two are against each other.

[0039] In this way, through the first plane, the transmission part and the first limiting part have a larger contact area at the position where the two are against each other, which is conducive to increasing the friction between the two and preventing slipping; in addition, the force between the two is relatively uniform, which is conducive to pushing the tool holder to slide smoothly; furthermore, by setting the first plane, the transmission part and the first limiting part have a larger overlapping range, which reduces the requirements for assembly accuracy. Even if there is a slight deviation in the position during assembly, the transmission part can still be in contact with the first limiting part;

[0040] Or / and, similarly, through the second plane, the friction between the positioning portion and the second limiting portion is greater and not easy to slip, and the force is relatively uniform, which is also conducive to promoting the tool holder to slide smoothly, and the assembly accuracy requirement is also relatively low.

[0041] In order to make the gear control member automatically move away from the knife holder so that the positioning part does not interfere with the second limiting part, the utility knife further includes a sliding part and a first elastic part;

[0042] The sliding member is slidably disposed in the accommodating cavity of the housing and is used to support the gear position control member;

[0043] The first elastic member extends along the abutment direction and is used to support the gear control member, so that the gear control member is away from the tool holder and the positioning part has a tendency not to interfere with the second limiting part. One end of the first elastic member abuts against the sliding member and the other end abuts against the gear control member.

[0044] In this way, after the external force acting on the shift operating member is removed, under the action of the first elastic member, the shift operating member automatically moves away from the tool holder and returns to a state where the positioning portion does not interfere with the second limiting portion, which is more labor-saving.

[0045] The first elastic member may have various structures. Preferably, the first elastic member is a first spring or a first elastic strip, one end of the first spring or the first elastic strip abuts against the sliding member and the other end abuts against the gear control member.

[0046] The sliding member may have various structures. Preferably, the sliding member is a sliding block or a sliding plate.

[0047] In order to allow the blade to automatically retract into the housing when not in use, the utility knife further comprises a second elastic member that causes the knife holder to slide backward and have a tendency to move backward toward the gear control member, the second elastic member extending along the sliding direction of the knife holder, one end of the second elastic member being connected to the knife holder, and the other end being connected to the sliding member or the inner wall of the housing;

[0048] Sliding the gear operating member backward can make its positioning portion contact and cooperate with the second limiting portion backward, or / and make the first limiting portion contact and cooperate with the transmission portion backward, or / and make the second elastic member act backward on the tool holder, thereby driving the tool holder to move backward.

[0049] In this way, after the external force acting on the safety control member is removed, under the action of the second elastic member, the knife holder automatically slides toward the rear of the shell, driving the blade to automatically retract into the shell, which is more labor-saving and also prevents the blade exposed from the shell from scratching the user himself or others.

[0050] The second elastic member may have various structures. Preferably, the second elastic member is a tension spring or a rubber ring, one end of which is connected to the tool holder, and the other end of which is connected to the sliding member or the inner wall of the housing.

[0051] In order to guide the sliding of the gear control member, the housing has a first slide groove connected to the accommodating cavity and located on the side, the head of the gear control member is located in the first slide groove, the first slide groove is used to guide the sliding of the gear control member, and the sliding track is located on the inner wall corresponding to the first slide groove. The gear control member can slide quickly through the guidance of the first slide groove.

[0052] In order to guide the sliding of the safety operating member, the housing has a second slide groove connected to the accommodating cavity and located on the top surface, the head of the safety operating member is located in the second slide groove, the second slide groove is used to guide the sliding of the safety operating member, and the extension length of the second slide groove corresponds to the extension length of the first slide groove. The safety operating member can slide quickly through the guidance of the second slide groove.

[0053] Compared with the prior art, the advantages of the present invention are: in the positioning direction, compared with the remaining areas on the sliding track except the first gear, the first gear is farther away from the positioning part of the gear control member, so that the gear control member can not only be used for gear switching, but also can resist and cooperate with the tool holder, thereby affecting whether the tool holder can slide forward independently, without the need to set a pin shaft, a pin hole, a retreating part, a supporting surface, an elastic element set on the lock pin to apply elastic force to the support surface and the retreating part, etc., and no elastic locking piece, a lock tongue, a supporting surface and a retreating part, etc., so that the utility knife of the present invention has fewer parts, so that the material cost is lower, the assembly process is less, and the assembly is more convenient and time-saving;

[0054] In addition, since the present invention does not have relatively small parts such as pins and lock tongues, the assembly accuracy requirements are relatively low, which also makes the assembly more convenient and time-saving, and parts are not easily lost. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a three-dimensional schematic diagram of an embodiment of the present invention;

[0056] Figure 2 yes Figure 1 Schematic diagram from another angle;

[0057] Figure 3 yes Figure 1 Schematic diagram after removing the left shell;

[0058] Figure 4 is an assembly diagram of a tool holder, a blade, a gear control member, a safety control member, a first elastic member, a second elastic member, etc. in an embodiment of the present invention (the first elastic member supports the gear control member to the left, the positioning portion of the gear control member is located in the first gear, the positioning portion and the second limiting portion do not overlap each other in the forward direction, and the gear control member does not interfere with the tool holder);

[0059] Figure 5 for Figure 4 Schematic diagram of another state (after the gear operating member is pressed to the right, the positioning portion of the gear operating member is disengaged from the first gear, the positioning portion of the gear operating member and the second limiting portion overlap each other in the forward direction, the gear operating member can resist and cooperate with the tool holder, and the safety operating member cannot slide);

[0060] Figure 6 An exploded view of an embodiment of the present invention;

[0061] Figure 7 for Figure 6 Schematic diagram from another angle;

[0062] Figure 8 for Figure 1 A schematic diagram from another angle;

[0063] Fig. 9 for Figure 8 Schematic diagram after removing the right shell;

[0064] Fig.10 for Fig. 9 Assembly drawings of the middle tool holder, blade, gear control member, safety control member, second elastic member, etc.;

[0065] Fig.11 is a three-dimensional schematic diagram of a tool holder in an embodiment of the present invention;

[0066] Fig.12 It is a schematic diagram of the assembly of the left housing, the gear position control member, the safety control member, the first elastic member, etc. in an embodiment of the present invention;

[0067] Fig.13 for Fig.12 Schematic diagram of the center left housing;

[0068] Fig.14 It is a cross-sectional view through the gear control member of an embodiment of the present invention (the gear control member is located in the first gear position, the positioning portion and the second limiting portion do not overlap each other in the forward direction, and the gear control member does not interfere with the tool holder);

[0069] Fig.15 for Fig.14 Schematic diagram of another state (the gear operating member is out of the first gear, the positioning portion and the second limiting portion overlap each other in the forward direction, the transmission portion and the first limiting portion overlap each other in the forward direction, and the gear operating member is in abutment with the tool holder);

[0070] Fig.16 for Fig.14 Schematic diagram of another state (the gear control member is located in the second gear position, the positioning portion and the second limiting portion overlap each other in the forward direction, the transmission portion and the first limiting portion overlap each other in the forward direction, and the gear control member is in conflict with the tool holder);

[0071] Fig.17 for Fig.14 Schematic diagram of another state (the gear control member is located between the two second gear positions, the positioning portion and the second limiting portion overlap each other in the forward direction, the transmission portion and the first limiting portion overlap each other in the forward direction, and the gear control member is in conflict with the tool holder);

[0072] Fig.18 It is a schematic diagram of the assembly of the tool holder, the limiting column, the third spring, etc. in the embodiment of the present invention. DETAILED DESCRIPTION

[0073] The present invention is further described in detail below with reference to the accompanying drawings.

[0074] like Figures 1 to 18 Shown is a preferred embodiment of the utility knife of the present invention.

[0075] The utility knife comprises main components such as a housing 1, a knife holder 2, a blade 3, a gear control member 4, a safety control member 5, a first elastic member 7, a second elastic member 8 and the like.

[0076] The housing 1 has a housing cavity 11, a front opening 12 connected to the housing cavity 11, a sliding track 13 arranged in the housing cavity 11 for the gear control member 4 to slide, a first slide groove 15 connected to the housing cavity 11, a second slide groove 16 connected to the housing cavity 11, and a rubber force application part 18 located at the top. For easy installation, the housing 1 includes a left housing 1a and a right housing 1b that can be matched with each other on the left and right sides, and the left housing 1a and the right housing 1b are matched to form the housing cavity 11. For easy cutting of the cable tie, the front bottom of the housing 1 also has a cutting opening 17 for the blade 3 to expose the blade.

[0077] The sliding track 13 may have different shapes, for example, it may be roughly a sliding plane, or the sliding track 13 may be uneven.

[0078] The sliding track 13 has a gear 14. The gear 14 includes a first gear 141 and two second gears 142 which are arranged on the sliding track 13 at intervals along the sliding direction A of the gear control member 4. The first gear 141 is arranged at the rear side of the housing 1, and the two second gears 142 are arranged at the front side of the first gear 141. Of course, the second gears 142 can also be set to different numbers as needed, such as 3 to 5 second gears 142; the first gear 141 can also be located between two of the second gears 142, and the number of the second gears 142 in the front and rear parts of the first gear 141 can be the same or different.

[0079] The housing 1 has a positioning direction B which is at an angle to the sliding direction A of the gear position operating member 4. Preferably, the sliding direction A is substantially perpendicular to the positioning direction B. In this embodiment, Figure 1 to Figure 3 It can be seen that the sliding direction A corresponds to the front-to-back direction, and the positioning direction B corresponds to the left-to-right direction. In the positioning direction B, compared with the remaining areas on the sliding rail 13 except the first gear 141 (in this embodiment, that is, the area on the sliding rail 13 within the two second gears 142 and between the first gear 141 and the frontmost second gear 142), the first gear 141 is farther away from the positioning part 42 of the gear control member 4.

[0080] The tool holder 2 is slidably disposed in the housing 11 of the housing 1. The tool holder 2 has a conflicting matching direction D which is at an angle to the advancing direction C of the tool holder 2. Figure 4-5 It can be seen that the advancing direction C corresponds to the front-rear direction, and the abutting and matching direction D is substantially perpendicular to the advancing direction C. The blade holder 2 is also provided with a magnetic steel 23 for adsorbing the blade 3, so that the blade 3 is not easy to slide off the blade holder 2.

[0081] The tool holder 2 has a first limiting portion 21 and a second limiting portion 22, wherein the first limiting portion 21 extends in the interference matching direction D, and the second limiting portion 22 is located at the rear side of the first limiting portion 21 and extends in the interference matching direction D. In addition, the back side of the tool holder 2 has a limiting groove 24, and a limiting column 800 and a third spring 9 sleeved outside the limiting column 800 are arranged between the limiting groove 24 and the inner wall of the housing 1. The limiting column 800 and the third spring 9 both extend in the interference matching direction D, and the head of the limiting column 800 is adapted to the limiting groove 24, one end of the third spring 9 abuts against the limiting column 800 and the other end abuts against the inner wall of the housing 1, and the third spring 9 has a tendency to support the limiting column 800 so that the head of the limiting column 800 is stuck in the limiting groove 24. By setting the limit column 800, there is a limiting effect on the tool holder 2. When the positioning portion 42 is in the first gear 141, if the utility knife is used abnormally or violently, the tool holder 2 is not easy to move forward independently because of the limitation of the tool holder 2 by the limit column 800, so that the blade 3 is not easy to be thrown out and injure the user himself or others.

[0082] The blade 3 is disposed on the blade holder 2 and can move in and out of the front opening 12 as the blade holder 2 slides forward and backward.

[0083] The gear position control member 4 has a transmission part 41 and a positioning part 42. The transmission part 41 does not interfere with the first position limiting part 21 or can conflict with the first position limiting part 21. The positioning part 42 is located at the rear side of the transmission part 41 and at the front side of the second position limiting part 22. The positioning part 42 has two functions: one is that the positioning part 42 is positioned and matched with the first gear position 141 and each second gear position 142, and the other is that the positioning part 42 does not interfere with the second position limiting part 22 or can conflict with the second position limiting part 22.

[0084] The process of interaction between the positioning portion and the first gear position 141 and the second gear position 142 is as follows.

[0085] Under the action of external force, the gear control member 4 can slide back and forth relative to the shell 1 and can make the positioning part 42 be located in different gears 14, correspondingly, the blade can enter and exit the front opening 12 of the shell 1 and can realize the positioning of the blade 3 extending out of the shell 1.

[0086] The positioning portion 42 can have a variety of shapes. In this embodiment, the positioning portion 42 is a positioning bump. The positioning portion 42 can also be a rod or a plate. The number of positioning portions 42 can be adjusted as needed. In this embodiment, in order to make the sliding of the gear control member 4 more stable, the number of positioning portions 42 is two, and the two positioning portions 42 are respectively located at the top and bottom of the gear control member 4 (from Figure 1 Correspondingly, there are also two groups of gear positions 14, and the two positioning portions 42 correspond to and cooperate with the two groups of gear positions 14 respectively.

[0087] When the positioning portion 42 of the shift control member 4 is located in the first gear position 141, the shift control member 4 does not interfere with the knife holder 2, and the knife holder 2 slides forward through the safety control member 5. Because when the positioning portion 42 of the shift control member 4 is located in the first gear position 141, the first limit portion 21 of the knife holder 2 is located in front of the positioning portion 42 of the shift control member 4 (the two may or may not overlap each other in the front-to-back direction at this time), and the second limit portion 22 of the knife holder 2 does not overlap with the positioning portion 42 of the shift control member 4 in the front-to-back direction. At this time, the safety control member 5 is slid forward and backward, and the knife holder 2 can slide forward and backward independently, so that the blade 3 on the knife holder 2 enters and exits the front opening 12 of the housing 1, that is, at this time, the shift control member 4 does not interfere with the front-to-back sliding of the knife holder 2, which corresponds to the safety mode of the utility knife.

[0088] When the positioning portion 42 of the gear position operating member 4 is located outside the first gear position 141 (in this embodiment, that is, when the positioning portion 42 has just left the first gear position 141 and has not yet slid along the sliding track 13, see Fig.15 Or the positioning portion 42 is located in the second gear 142, for example Fig.16 or the positioning portion 42 is located in the area on the sliding track 13 between the first gear 141 and the second gear 142 that is closest to the front, for example Fig.17 ), the gear control member 4 can cooperate with the tool holder 2, and the tool holder can slide forward through the gear control member 4. The "can cooperate with the tool holder" here means: it is necessary to push the gear control member 4 to move forward, so that the gear control member 4 and the tool holder 2 are in conflict, and the tool holder 2 is pushed forward. When the positioning portion 42 of the gear control member 4 has just left the first gear 141 and has not yet slid forward along the sliding track 13, the gear control member 4 and the tool holder 2 may not be in contact with each other, but the tool holder can no longer slide forward independently (because the positioning portion 42 of the gear control member 4 blocks the second limiting portion 22 of the tool holder 2 in front); it can also be that when the positioning portion 42 of the gear control member 4 has just left the first gear 141 and has not yet slid forward along the sliding track 13, the gear control member 4 and the tool holder 2 are already in contact with each other, and the tool holder 2 can no longer slide forward independently.

[0089] The first gear position 141, the second gear position 142 and the positioning portion 42 may have different shapes. In this embodiment, the first gear position 141 is a first groove formed by the sliding track 13 being recessed in the positioning direction B for accommodating the positioning portion 42, and the second gear position 142 is a second groove formed by the sliding track 13 being recessed in the positioning direction B for accommodating the positioning portion 42. In the positioning direction B, the groove depth of the first groove is greater than the groove depth of each second groove, so that in the positioning direction B, compared with the remaining area on the sliding track 13 except the first groove, the groove bottom of the first groove is farther away from the positioning portion 42 of the gear control member 4. The positioning portion 42 may be a positioning protrusion.

[0090] In other embodiments, the first gear position 141 may be the first positioning protrusion, and the second gear position 142 may be the second positioning protrusion. In the positioning direction B, the first positioning protrusion is farther away from the tool holder 2 than the second positioning protrusions, and a groove adapted to the first positioning protrusion and the second positioning protrusion is provided on the gear operating member 4.

[0091] In addition, the action process of the positioning portion 42 on the second limiting portion 22 is as follows.

[0092] The main principle is that the positioning portion 42 interacts with the second limiting portion 22 .

[0093] When the positioning portion 42 of the gear position control member 4 is located in the first gear position 141, see Fig.14 The transmission part 41 does not interfere with the first limiting part 21, the positioning part 42 and the second limiting part 22 do not overlap each other in the advancing direction C, and the sliding safety control member 5 can drive the knife holder 2 to slide forward and backward, thereby driving the blade 3 to enter and exit the front opening 12;

[0094] When the positioning portion 42 of the gear position control member 4 is not located in the first gear position 141 (that is, when the positioning portion 42 has just left the first gear position 141 and has not yet slid along the sliding track 13, see Fig.15 Or the positioning portion 42 is located in each second gear 142, for example Fig.16 or the positioning portion 42 is located in the area on the sliding track 13 between the first gear 141 and the second gear 142 that is closest to the front, for example Fig.17 ), the transmission part 41 and the first limit part 21 partially overlap each other in the forward direction C, the positioning part 42 and the second limit part 22 partially overlap each other in the forward direction C, and the gear control member 4 is slid forward to enable the transmission part 41 to move forward and cooperate with the first limit part 21, thereby driving the tool holder 2 to move forward and preventing the tool holder 2 from resetting backward alone.

[0095] Sliding the gear operating member 4 backwards to drive the tool holder 2 to move backwards can be achieved by combining one or more of the following three methods: the positioning portion 42 contacts and cooperates with the second limiting portion 22 backwards, the first limiting portion 21 contacts and cooperates with the transmission portion 41 backwards, and the second elastic member 8 acts backwards on the tool holder 2. In this embodiment, sliding the gear operating member 4 backwards can be achieved by the positioning portion 42 contacting and cooperating with the second limiting portion 22 backwards, thereby driving the tool holder 2 to move backwards.

[0096] In order to facilitate user operation, the head of the gear control member 4 is located in the first slide groove 15 on the side of the housing 1, and the first slide groove 15 is used to guide the sliding of the gear control member 4, and the sliding track 13 is located on the inner wall corresponding to the first slide groove 15. The head of the gear control member 4 can be a rubber sleeve with convex points to increase friction.

[0097] In order to prevent the tool holder 2 from sliding forward independently immediately after the external force acts on the gear operating member 4, when the positioning portion 42 of the gear operating member 4 is located in the first gear 141, the positioning portion 42 and the second limiting portion 22 approach each other in the interference matching direction D and the distance between them is small. In this way, when the external force begins to act on the gear operating member 4, the positioning portion 42 originally located in the first gear 141 moves toward the tool holder 2 in the interference matching direction D. Because the distance is small, the positioning portion 42 can immediately approach each other with the second limiting portion 22 in the forward direction C, that is, the gear operating member 4 can immediately prevent the tool holder 2 from sliding forward independently. At this time, if the utility knife is not used normally or violently, the blade 3 set on the tool holder 2 will not be thrown out, and the safety is higher. In order to make the blade 3 more sensitive to telescopic reaction, when the positioning part 42 is located in the first gear 141, the transmission part 41 and the first limiting part 21 have partially overlapped in the forward direction C, so that the gear control member 4 can be operated without jamming and has a good hand feel, and the transmission part 41 and the first limiting part 21 have a smaller distance between them in the forward direction C of the tool holder 2; when the positioning part 42 and the second limiting part 22 partially overlap each other in the forward direction C, the positioning part 42 and the second limiting part 22 are close to each other in the forward direction C of the tool holder 2 and the front-to-back distance between them is smaller; in this way, the forward and backward sliding of the gear control member 4 can be immediately reflected as the telescopic reaction of the blade 3, almost without delay, so that the telescopic reaction of the blade 3 is more sensitive. In this embodiment, the first limiting part 21 is the first plane X at the position where it abuts against the transmission part 41; in other embodiments, the first plane X can also be set on the transmission part 41, or the transmission part 41 and the first limiting part 21 can both have the first plane X. In this embodiment, the positioning part 42 and the second limiting part 22 are both the second plane Y at the position where the two are against each other; in other embodiments, one of the positioning part 42 and the second limiting part 22 may have the second plane Y at the position where the two are against each other. In this way, through the first plane X, the contact area between the transmission part 41 and the first limiting part 21 at the position where the two are against each other is larger, which is conducive to increasing the friction between the two and not easy to slip; in addition, the force between the two is relatively uniform, which is conducive to pushing the tool holder 2 to slide smoothly; furthermore, by setting the first plane X, the overlapping range of the transmission part 41 and the first limiting part 21 is larger, which reduces the requirements for assembly accuracy. Even if there is a slight deviation in the position during assembly, the transmission part 41 can still not interfere with the first limiting part 21 or conflict with the first limiting part 21. Similarly, through the second plane Y, the friction between the positioning part 42 and the second limiting part 22 is larger and not easy to slip, the force is relatively uniform, which is also conducive to pushing the tool holder 2 to slide smoothly, and the requirements for assembly accuracy are also relatively low.

[0098] The safety operating member 5 is disposed on the blade holder 2, and is used to drive the blade holder 2 to slide forward and backward, thereby driving the blade 3 to move forward and backward in and out of the front opening 12. The head of the safety operating member 5 is located in the second slide groove 16 at the top of the housing 1, and the second slide groove 16 is used to guide the sliding of the safety operating member 5, and the extension length of the second slide groove 16 corresponds to the extension length of the first slide groove 15 of the housing 1.

[0099] The sliding member 6 is slidably disposed in the accommodating cavity 11 of the housing 1 and is used to support the gear operating member 4. In this embodiment, the sliding member 6 is a sliding block, and the sliding block has a blocking arm 61 for pushing the tool holder 2 to move forward; in other embodiments, the size and shape of the sliding member 6 can also be adjusted as needed, for example, the sliding member 6 can also be a sliding plate.

[0100] The first elastic member 7 extends along the abutment matching direction D and is used to support the shift control member 4, so that the shift control member 4 is away from the tool holder 2 and the positioning portion 42 has a tendency not to interfere with the second limiting portion 22. One end of the first elastic member 7 abuts against the sliding member 6 and the other end abuts against the shift control member 4. Preferably, in this embodiment, the first elastic member 7 is a first spring, and of course the first spring can also be replaced by a first elastic strip, one end of the first spring abuts against the sliding member 6 and the other end abuts against the shift control member 4.

[0101] The second elastic member 8 makes the tool holder 2 slide backward and has a tendency to move backward close to the gear control member 4. The second elastic member 8 extends along the sliding direction A of the tool holder 2. One end of the second elastic member 8 is connected to the tool holder 2, and the other end is connected to the sliding member 6 or the inner wall of the housing 1. In this embodiment, the second elastic member 8 is a tension spring, one end of which is connected to the tool holder 2, and the other end is connected to the sliding member 6. In other embodiments, the second elastic member may also be a rubber ring or other shapes, and the other end of the tension spring may also be directly connected to the inner wall of the housing 1.

[0102] It can be seen that in this embodiment, the gear control member 4 has no interference with the tool holder 2 or can cooperate with the tool holder 2 through the interaction of the first gear 141, the second gear 142, the first limit part 21, the second limit part 22, the transmission part 41, the positioning part 42, the sliding member 6, the first elastic member 7 and the second elastic member 8, thereby affecting whether the safety operating member 5 can independently drive the tool holder 2 to slide forward and backward.

[0103] In addition, in order to facilitate the replacement of the blade 3, a blade-changing switch 400 is provided on the housing 1. The blade-changing switch 400 and the blade 3 can adopt the existing technology. For example, a bayonet 31 is provided on the top of the blade 3, and an elastic locking piece 300 is provided on the back of the tool holder 2. The elastic locking piece 300 has a first flange 301 and a second flange 302 located above the first flange 301. The first flange 301 is locked with the bayonet 31. When the blade 3 is locked with the first flange 301, the second flange 302 is located above the blade 3. The second flange 302 cooperates with the tool-changing switch 400, and the tool-changing switch 400 is movably arranged on the housing 1. One end of the tool-changing switch 400 is located in the accommodating cavity 11 of the housing 1, and the other end of the tool-changing switch 400 extends out of the housing 1. A sixth spring 500 is arranged between the tool-changing switch 400 and the housing 1. The sixth spring 500 makes the tool-changing switch 400 have a tendency to move away from the second flange 302 of the elastic locking sheet 300. One end of the sixth spring 500 abuts against the housing 1 and the other end abuts against the tool-changing switch 400.

[0104] In order to facilitate the replacement of the worn blade 3, the utility knife further includes a spare blade 600, and the matching structure of the spare blade 600 and the housing 1 can adopt the existing technology. For example, the housing 1 also has a top opening 19 connected to the accommodating cavity 11, and the utility knife further includes a mounting seat 700 that can partially enter and exit the top opening 19, a locking switch 100 that locks the mounting seat 700 in a state of being located in the accommodating cavity 11, and a fourth elastic member 200 that makes the mounting seat 700 have a tendency to pop out of the housing 1. The spare blade 600 is detachably mounted on the mounting seat 700. The locking switch 100 includes a locking block 101 and a fifth elastic member 102. One end of the locking block 101 abuts against the card slot 701 on the mounting seat 700. The other end of the locking block 101 abuts against one end of the fifth elastic member 102. The other end of the fifth elastic member 102 is connected to the housing 1. The top of the locking block 101 extends out of the housing 1. The fifth elastic member 102 has the function of restoring one end of the locking block 101 to a state of abutting against the card slot 701. The fifth elastic member 102 and the fourth elastic member 200 can both be springs or elastic strips.

[0105] The working principle and usage of the utility knife are as follows.

[0106] (1) When using safe mode, Figure 1 to Figure 4 , Fig.14 At this time, the first elastic member 7 supports the gear operating member 4, and the positioning portion 42 of the gear operating member 4 is located in the first gear 141. At this time, the positioning portion 42 and the second limiting portion 22 do not overlap each other in the forward direction C. The safety operating member 5 slides forward and backward to drive the knife holder 2 to slide forward and backward, thereby driving the blade 3 to enter and exit the front opening 12, that is, the gear operating member 4 does not interfere with the knife holder 2;

[0107] When the safety operating member 5 is released, the blade holder 2 automatically moves toward the shift operating member 4 under the action of the second elastic member 8, thereby driving the blade 3 to automatically retract into the accommodating chamber 11 of the housing 1 to prevent the exposed blade 3 from scratching the user or others.

[0108] (2) When you need to switch to gear 14, refer to Fig.15 , into the housing 1 (from Figure 1 In the embodiment of FIG. 1 , the shift control member 4 is pressed to the right (i.e., to move the shift control member 4 to the right), so that the positioning portion 42 of the shift control member 4 is separated from the first gear 141 and does not slide forward, the positioning portion 42 and the second limiting portion 22 of the tool holder 2 partially overlap each other in the forward direction C, and the safety control member 5 cannot slide forward and cannot independently drive the tool holder 2 to slide forward. In addition, because the external force does not act on the shift control member 4, the positioning portion 42 and the second limiting portion 22 are close to each other in the conflicting matching direction D and the distance between the two is small. In this way, when the external force starts to press the shift control member 4 to the right without pushing the shift control member 4 forward, the positioning portion 42 originally located in the first gear 141 can immediately overlap with the second limiting portion 22 in the forward direction C, that is, the shift control member 4 can immediately prevent the tool holder 2 from sliding forward independently. At this time, if the utility knife is not used normally or violently, the blade 3 will not be thrown out and the safety is high.

[0109] Next, the gear operating member 4 is pushed forward, and the transmission portion 41 of the gear operating member 4 and the first limiting portion 21 of the knife holder 2 are in front and back contact, thereby pushing the knife holder 2 to move forward, and the blade 3 gradually extends out of the housing 1 until the positioning portion 42 is positioned at the corresponding second gear position 142. When the positioning portion 42 is in the second gear position 142, the gear operating member 4 and the knife holder 2 also maintain a state of being able to contact each other front and back;

[0110] The gear operating member 4 is pushed backward, so that the positioning portion 42 thereof can be opposed and matched with the second limiting portion 22, thereby driving the blade holder 2 to move backward, and the second elastic member 8 also causes the blade holder 2 to move backward, so that the blade 3 is gradually retracted into the accommodating cavity 11 of the housing 1; when the gear operating member 4 is pushed to the corresponding second gear position 142, the gear operating member 4 and the blade holder 2 can still maintain a state of being able to contact each other from front to back;

[0111] In the process of pushing the shift operating member 4 forward or backward (see Fig.16 , Fig.17 ), the positioning portion 42 of the gear operating member 4 is located on the position of the sliding track 13 to adjust the extension range of the blade 3 from the housing 1. When the positioning portion 42 of the gear operating member 4 is located in the two second gears 142, the extension range of the blade 3 is fixed. At this time, the blade 3 can be used to cut paper, leather, etc. When cutting, the index finger can be placed on the rubber force-applying portion 18, so that the index finger feels better and it is effortless to use.

[0112] That is to say, except when the positioning portion 42 of the gear position operating member 4 is located in the first gear position 141 ( Fig.14 ), the gear control member 4 does not interfere with the blade holder 2, and the safety control member 5 is pushed to drive the blade 3 to enter and exit the front opening 12. The gear control member 4 is located in other positions (that is, when the positioning portion 42 has just left the first gear 141 and has not yet slid along the sliding track 13, see Fig.15 Or the positioning portion 42 is located in each second gear 142, for example Fig.16 or the positioning portion 42 is located in the area on the sliding track 13 between the first gear 141 and the second gear 142 that is closest to the front, for example Fig.17 ), the gear control member 4 can cooperate with the tool holder 2, and the gear control member 4 can be slid forward and backward to correspondingly drive the safety control member 5 and the tool holder 2 to slide forward and backward synchronously. At this time, the safety control member 5 cannot be slid forward and backward alone, and the safety control member 5 cannot independently drive the tool holder 2 to slide forward and backward.

[0113] (3) When the blade 3 needs to be replaced, the blade holder 2 is moved forward to be fully extended under the push of the shift control member 4. At this time, the blade change switch 400 is exactly aligned with the second flange 302 of the lock plate 300. By pressing the blade change switch 400, the blade change switch 400 abuts against the second flange 302 and pushes the second flange 302 inward, driving the first flange 301 to disengage from the retaining hole 31 of the blade 3. At this time, the blade 3 is pulled outward to be removed from the blade holder 2.

[0114] The locking block 101 is pushed, and under the action of the fourth elastic member 200, a part of the mounting seat 700 pops out from the top opening 19, and the spare blade 600 is removed from the mounting seat 700. Then, the mounting seat 700 is acted on again to restore the mounting seat 700 to a state of being located in the accommodating cavity 11, and the locking block 101 is located in the card slot 701 to lock the mounting seat 700;

[0115] Continue to press the tool change switch 400 inward, then place the spare blade 600 on the tool holder 2 from the front opening 12, and then release the tool change switch 400. At this time, the first flange 301 returns to the position of the snap-in slot 31 to position the spare blade 600 on the tool holder 2.

[0116] (4) When the cable tie needs to be cut, place the cable tie on the blade of the cutting opening 17 and move the cable tie back and forth.

Claims

1. A utility knife, comprising A housing (1) comprising a housing cavity (11), a front opening (12) communicating with the housing cavity (11), and a sliding track (13) arranged in the housing cavity (11) for sliding a gear position operating member (4) described below, wherein the sliding track (13) has gear positions (14), wherein the gear positions (14) include a first gear position (141) and at least one second gear position (142) arranged on the sliding track (13) at intervals along a sliding direction (A) of the gear position operating member (4) described below; A tool holder (2) is slidably disposed in the accommodating cavity (11) of the housing (1); A blade (3) is arranged on the blade holder (2) and can move in and out of the front opening (12) as the blade holder (2) slides; The gear position control member (4) has a positioning portion (42) that is positioned and matched with the first gear position (141) and each second gear position (142); under the action of an external force, the gear position control member (4) can slide forward and backward relative to the housing (1) and can make the positioning portion (42) be located in different gear positions (14), so that the blade (3) can enter and exit the front opening (12) of the housing (1) and can achieve the positioning of the blade (3) extending out of the housing (1); A safety control member (5) is arranged on the blade holder (2) and is used to drive the blade holder (2) to slide forward and backward so as to drive the blade (3) to move forward and backward in and out of the front opening (12); Features: The housing (1) has a positioning direction (B) that is at an angle to the sliding direction (A) of the gear operating member (4); in the positioning direction (B), compared with the remaining areas on the sliding track (13) except the first gear (141), the first gear (141) is further away from the positioning portion (42) of the gear operating member (4); When the positioning portion (42) of the gear operating member (4) is located in the first gear position (141), the gear operating member (4) does not interfere with the tool holder (2), and the tool holder (2) slides forward through the safety operating member (5); When the positioning portion (42) of the gear operating member (4) is located in a position other than the first gear position (141), the gear operating member (4) can resist and cooperate with the tool holder (2), and the tool holder (2) can slide forward through the gear operating member (4).

2. The utility knife according to claim 1, characterized in that: The first gear position (141) is a first groove formed by the sliding track (13) being recessed in the positioning direction (B) and used to accommodate the positioning portion (42); the second gear position (142) is a second groove formed by the sliding track (13) being recessed in the positioning direction (B) and used to accommodate the positioning portion (42); in the positioning direction (B), the groove depth of the first groove is greater than the groove depth of each second groove, so that in the positioning direction (B), compared with the remaining area on the sliding track (13) except the first groove, the groove bottom of the first groove is farther away from the positioning portion (42) of the gear control member (4); The positioning portion (42) is a positioning protrusion.

3. The utility knife according to claim 1, characterized in that: The tool holder (2) has a conflicting matching direction (D) which is at an angle to the advancing direction (C) of the tool holder (2); The tool holder (2) comprises a first limiting portion (21) and a second limiting portion (22), wherein the first limiting portion (21) extends in the interference matching direction (D), and the second limiting portion (22) is located at the rear side of the first limiting portion (21) and extends in the interference matching direction (D); The gear position control member (4) has a transmission portion (41), and the positioning portion (42) is located at the rear side of the transmission portion (41) and at the front side of the second limiting portion (22); When the positioning portion (42) of the gear operating member (4) is located in the first gear position (141), the transmission portion (41) does not interfere with the first limiting portion (21), the positioning portion (42) and the second limiting portion (22) do not overlap each other in the forward direction (C), and the sliding safety operating member (5) can drive the knife holder (2) to slide forward and backward, thereby driving the blade (3) to enter and exit the front opening (12); When the positioning portion (42) of the gear operating member (4) is located in the first gear position (141), the transmission portion (41) and the first limiting portion (21) at least partially overlap each other in the forward direction (C), and the positioning portion (42) and the second limiting portion (22) at least partially overlap each other in the forward direction (C). When the gear operating member (4) is slid forward, the transmission portion (41) can be moved forward to contact and cooperate with the first limiting portion (21), thereby driving the tool holder (2) to move forward and preventing the tool holder (2) from resetting backward on its own.

4. The utility knife according to claim 3, characterized in that: When the positioning portion (42) of the gear control member (4) is located in the first gear position (141), the positioning portion (42) and the second limiting portion (22) are close to each other in the interference matching direction (D) and the distance between them is small.

5. The utility knife according to claim 3, characterized in that: When the positioning portion (42) is located in the first gear position (141), the transmission portion (41) and the first limiting portion (21) partially overlap in the forward direction (C), and at this time, the distance between the transmission portion (41) and the first limiting portion (21) in the forward direction (C) of the tool holder (2) is relatively small; or / and, when the positioning portion (42) and the second limiting portion (22) at least partially overlap each other in the advancing direction (C), the positioning portion (42) and the second limiting portion (22) are close to each other in the advancing direction (C) of the tool holder (2) and the distance between them is small; Or / and, the back side of the tool holder (2) has a limiting groove (24), a limiting column (800) and a third spring (9) sleeved on the limiting column (800) are arranged between the limiting groove (24) and the inner wall of the shell (1), the head of the limiting column (800) is adapted to the limiting groove (24), one end of the third spring (9) is against the limiting column (800) and the other end is against the inner wall of the shell (1), and the third spring (9) has a tendency to support the limiting column (800) and make the head of the limiting column (800) snap into the limiting groove (24).

6. The utility knife according to claim 3, characterized in that: At least one of the transmission portion (41) and the first limiting portion (21) forms a first plane (X) at a position where the two abut against each other; Or / and, at least one of the positioning portion (42) and the second limiting portion (22) forms a second plane (Y) at a position where the two abut against each other.

7. The utility knife according to claim 3, characterized in that: The utility knife further comprises a sliding member (6) and a first elastic member (7); The sliding member (6) is slidably disposed in the accommodating cavity (11) of the housing (1) and is used to support the gear position control member (4); The first elastic member (7) extends along the abutment-matching direction (D) and is used to support the gear control member (4), so that the gear control member (4) is away from the tool holder (2) and the positioning portion (42) has a tendency not to interfere with the second limiting portion (22). One end of the first elastic member (7) abuts against the sliding member (6) and the other end abuts against the gear control member (4).

8. The utility knife according to claim 7, characterized in that: The first elastic member (7) is a first spring or a first elastic strip, one end of which abuts against the sliding member (6) and the other end of which abuts against the gear position control member (4).

9. The utility knife according to claim 7, characterized in that: The sliding member (6) is a sliding block or a sliding plate.

10. The utility knife according to claim 3, characterized in that: The utility knife further comprises a second elastic member (8) which causes the knife holder (2) to slide backward and has a tendency to move backward toward the gear control member (4); the second elastic member (8) extends along the sliding direction (A) of the knife holder (2); one end of the second elastic member (8) is connected to the knife holder (2), and the other end is connected to the sliding member (6) or the inner wall of the housing (1); Sliding the gear operating member (4) backward can cause the positioning portion (42) to contact and cooperate with the second limiting portion (22) backward, or / and cause the first limiting portion (21) to contact and cooperate with the transmission portion (41) backward, or / and cause the second elastic member (8) to act backward on the tool holder (2), thereby driving the tool holder (2) to move backward.

11. The utility knife according to claim 10, characterized in that: The second elastic member (8) is a tension spring or a rubber ring, one end of which is connected to the tool holder (2) and the other end of which is connected to the sliding member (6) or the inner wall of the housing (1).

12. The utility knife according to any one of claims 1 to 11, characterized in that: The housing (1) has a first slide groove (15) connected to the accommodating cavity (11) and located on the side surface; the head of the gear operating member (4) is located in the first slide groove (15); the first slide groove (15) is used to guide the sliding of the gear operating member (4); and the sliding track (13) is located on the inner wall corresponding to the first slide groove (15).

13. The utility knife according to claim 12, characterized in that: The housing (1) has a second slide groove (16) connected to the accommodating cavity (11) and located on the top surface. The head of the safety operating member (5) is located in the second slide groove (16). The second slide groove (16) is used to guide the sliding of the safety operating member (5). The extension length of the second slide groove (16) corresponds to the extension length of the first slide groove (15).

Images