Knife pouch for processing machine and injection mold for manufacturing knife pouch body

Abstract

The invention relates to a knife pouch for a processing machine and an injection mold for manufacturing a knife pouch body. The knife pouch for the processing machine comprises the knife pouch body, a knife locking device and a positioning block, wherein the knife pouch body is provided with a sleeve hole for a taper shank of a knife handle to insert; the cutter locking device is used for providing a radial force for the taper shank inserted into the sleeving hole; the positioning block is provided with a positioning part which is exposed in the sleeving hole in a protruding mode, and the positioning part is embedded in the positioning groove of the knife handle, so that the knife handle cannot rotate relative to the knife pouch body. Besides, an injection mold can be used for manufacturing the knife pouch body, the injection mold can be used for producing multiple types of knife pouch bodies by adjusting the positions of part of components, and the positioning structures of different types of knife pouch bodies are positioned in different directions, so that the cost of using multiple pairs of molds can be greatly reduced.

Description

Technical Field

[0001] This invention relates to a storage structure for a tool holder used in a composite machining machine, and in particular to a tool holder for a machining machine and an injection mold for manufacturing the tool holder body. Background Technology

[0002] The tool holder, or tool shank, used in machining centers serves as a bridge between the machine tool spindle and the cutting tool. In computer-controlled machining programs, to smoothly perform machining operations such as drilling, milling, boring, and turning, the cutting tool attached to the tool holder varies. Common cutting tools include milling cutters, reamers, boring tools, backreamers, and turning inserts. Furthermore, to meet complex machining requirements, the machining center is equipped with a tool magazine and a tool changing mechanism. The tool magazine provides multiple tool holders for multiple tool holders, each with a different cutting tool attached. The tool changing mechanism is used to quickly exchange the tool holders (along with the cutting tools) located in the tool magazine with those on the machine tool spindle, thereby improving work efficiency.

[0003] To ensure machining accuracy, a tool setting point (or workpiece origin) must be selected before machining for subsequent tool setting procedures. Tool setting refers to the requirement that the tool setting point coincide with the tool position point. The purpose is to determine the absolute coordinates of the tool setting point in the machine tool coordinate system, used to measure the tool position deviation. The tool setting point refers to the starting point of the tool's movement relative to the workpiece during machining on a CNC machine tool. The tool setting point can be set on the workpiece, the fixture, or the machine tool. The tool position point refers to the tool's positioning reference point; for example, for turning inserts, the tool position point is at the tool tip. As mentioned above, the tool position point is extremely important in automated machining programs, and the tool position points of different tools are set according to different machining programs. Therefore, to ensure that the tool position points of each tool in the tool magazine are maintained in the preset positions so that the tool changer can retrieve the correct tool, the existing method is to manufacture the tool holder body, which constitutes one of the tool holders, in multiple ways. This provides a tool holder for fixing different tools, which is then inserted and positioned to stabilize the tool position point. However, this method increases the production cost of the sheath body, especially when the sheath body is made by injection molding, multiple special molds are required to produce the aforementioned sheath bodies, which will inevitably increase the cost expenditure. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a tool holder for a processing machine and an injection mold for manufacturing the tool holder body, wherein the tool holder can stably store the tool handle and prevent improper rotation of the tool handle, and the injection mold can be used to produce multiple types of tool holder bodies, and the positioning structure of different types of tool holder bodies is located in different positions.

[0005] To achieve the above objectives, the present invention provides a knife sheath comprising a knife sheath body, a locking device, and a positioning block. The knife sheath body has a socket with a virtual axis defined through its center, and the socket allows a tapered shank of a knife handle to be inserted. The locking device provides a radial force to the tapered shank inserted into the socket. The positioning block is fixed to the knife sheath body and has a positioning portion protruding from the socket. Thus, when the tapered shank of the knife handle is inserted into the socket, the positioning portion of the positioning block engages with the positioning groove of the knife handle, preventing the knife handle from rotating relative to the knife sheath body around the axis.

[0006] The injection mold provided by this invention can produce a die holder body having an internal partition wall and a fitting hole. The partition wall has a mounting hole that connects the fitting hole to the outside of the die holder body. The injection mold includes a molding base, a first slider, and a second slider. The molding base includes a first half mold and a second half mold. Each half mold has a parting surface and an inner surface recessed from the parting surface. When the parting surface of the first half mold engages with the parting surface of the second half mold, the inner surface of the first half mold and the inner surface of the second half mold together form a cavity. The first slider and the second slider are movable relative to the molding die base from both sides along a virtual baseline between an inserted position and an uninserted position. The first slider has a first end face and a parting post protruding from the first end face and offset from the baseline. The second slider has a conical post with a second end face. When the first half-mold and the second half-mold are closed and the first slider and the second slider are in the inserted position, the parting post and the conical post are located in the cavity, and a gap is separated between the first end face and the second end face. The parting post forms the mounting hole of the die holder body, the conical post forms the socketing hole of the die holder body, and the gap between the first end face and the second end face forms the partition wall of the die holder body.

[0007] In this way, by adjusting the first and second sliders located in the uninserted position and rotating them around the baseline at several fixed points, the injection mold can produce multiple types of tool holder bodies, with the positioning structures of different types of tool holder bodies located in different orientations. This can significantly reduce the cost of using multiple molds. Attached Figure Description

[0008] Figure 1 This is a perspective view of a machining tool holder and tool handle according to a preferred embodiment of the present invention;

[0009] Figure 2 This is an exploded view of the machining tool holder of the preferred embodiment of the present invention.

[0010] Figure 3 for Figure 2A sectional view of the blade sheath body;

[0011] Figure 4 for Figure 3 4-4 sectional view;

[0012] Figure 5 for Figure 3 Sectional view in direction 5-5;

[0013] Figure 6 for Figure 1 The cross-sectional view shown is of the blade sheath and handle combined.

[0014] Figure 7 for Figure 6 Sectional view in direction 7-7;

[0015] Figure 8 for Figure 7 8-8 sectional view;

[0016] Figure 9 for Figure 7 A 9-9 sectional view reveals that the positioning block is located on the left side;

[0017] Figure 10 A perspective view of an injection mold for manufacturing a blade sheath body according to a preferred embodiment of the present invention;

[0018] Figure 11 for Figure 10 A perspective view of the injection mold from another angle;

[0019] Figure 12 for Figure 10 A simplified diagram of the molding die base in the injection mold shown;

[0020] Figure 13 for Figure 10 A schematic diagram showing the mold closing state of the injection mold;

[0021] Figure 14 for Figure 13 A schematic diagram of a cross-section of an injection mold in the closed state.

[0022] Figure 15 Similar Figure 10 This reveals the state in which the first and second sliders in the injection mold are flipped ninety degrees;

[0023] Figure 16 Similar Figure 9 This reveals that the positioning block is located at the top;

[0024] Figure 17 Similar Figure 9 This reveals that the positioning block is located on the right side;

[0025] Figure 18 Similar Figure 9 This reveals that the positioning block is located below.

[0026] [Symbol Explanation]

[0027] 100: Knife Sheath

[0028] 10,10A,10B,10C: Knife holder body

[0029] 10a: Top

[0030] 10b: Bottom

[0031] 12: Partition wall

[0032] 12a: Axial hole

[0033] 12b: Radial hole

[0034] 12c: Mounting hole

[0035] 12d: Through hole

[0036] 14: Socket

[0037] 14a: Inner convex part

[0038] 14b: concave part

[0039] 16: Stop surface

[0040] 20: Positioning Block

[0041] 22: Positioning Department

[0042] 30: Knife locking device

[0043] 31: Shaft tube

[0044] 31a: Side opening

[0045] 31b: retaining wall

[0046] 32: Steel balls

[0047] 33: Unlocking Item

[0048] 33a: Top Pushing Section

[0049] 33b: Screw hole

[0050] 34: Spring

[0051] 35: Screws

[0052] 36: Gasket

[0053] 37: Baffle

[0054] 37a: Perforation

[0055] 38: Bolt

[0056] 200: Knife handle

[0057] 201: Tapered Handle

[0058] 201a: End face

[0059] 201b: Peripheral surface

[0060] 201c: Outer convex part

[0061] 202: Shaft Hole

[0062] 203: Annular groove

[0063] 204: Positioning groove

[0064] 300: Injection mold

[0065] 301: First Opening

[0066] 302: Second opening

[0067] 303: Injection port

[0068] 310: Molding mold base

[0069] 311: First Half-Model

[0070] 311a: Parting surface

[0071] 311b: Inner surface

[0072] 312: Second half mold

[0073] 312a: Parting surface

[0074] 312b: Inner surface

[0075] 320: First slider

[0076] 321: First end face

[0077] 322: Fractal Column

[0078] 330: Second slider

[0079] 331: Conical prism

[0080] 332: Outer peripheral surface

[0081] 333: Second end face

[0082] 334: Central Pillar

[0083] 335: Extended Column

[0084] L: Axis

[0085] L1: Baseline

[0086] L2: Vertical line

[0087] P1: Uninserted position

[0088] P2: Insertion position

[0089] S: Cavity

[0090] T: Contact point

[0091] W: Spacing Detailed Implementation

[0092] Given that the tool position points of different cutting tools are different, the tool holder provided by the present invention can not only produce a good positioning effect for the stored tool handle, but also the tool holder body, one of its components, has a positioning structure through the processing of an injection mold. This positioning structure provides a positioning block to prevent the tool handle from rotating, so as to ensure that the tool position point of the tool fixed on the tool handle is kept in the set position, which is convenient for a subsequent tool changing mechanism to pick up according to the processing program.

[0093] The following description uses a preferred embodiment of the blade holder of the present invention to achieve the above-mentioned objectives. Please refer to... Figure 1 As shown, the preferred embodiment of the present invention, the tool holder 100, is suitable for storing the tool handle 200 used in a composite processing machine. The tool handle 200 has a tapered shank 201, the tapered shank 201 has an end face 201a and an outer peripheral face 201b, the tool handle 200 has a shaft hole 202 recessed from the end face 201a, and a recessed annular groove 203 is provided on the hole wall of the shaft hole 202, and a positioning groove 204 is provided at the connection between the end face 201a and the outer peripheral face 201b.

[0094] Please cooperate. Figure 2 As shown, the aforementioned blade sheath 100 includes a blade sheath body 10, a positioning block 20, and a blade locking device 30. Please also consider... Figures 3 to 5As shown, the blade sheath body 10 is an injection-molded hollow molded product, which has a partition wall 12 inside and a fitting hole 14 is formed on one side of the partition wall 12. The partition wall 12 has an axial hole 12a and a radial hole 12b. One end of the axial hole 12a is connected to the socket hole 14, and the other end is connected to the outside of the blade holder body 10. One end of the radial hole 12b is connected to the axial hole 12a, and the other end is connected to the outside of the blade holder body 10. The partition wall 12 also has a mounting hole 12c and four through holes 12d. The mounting hole 12c and the through holes 12d are arranged parallel to the axial hole 12a, and one end of each of them is connected to the socket hole 14, and the other end is connected to the outside of the blade holder body 10. The blade holder body 10 further forms a stop surface 16 at the connection between the hole wall of the mounting hole 12c and the hole wall of the socket hole 14. In addition, a virtual axis L is defined passing through the center of the socket hole 14 and the axial hole 12a. The blade handle 200 inserts the tapered shank 201 into the socket hole 14 along the axis L.

[0095] In this embodiment, the positioning block 20 is a long strip made of medium carbon steel. The positioning block 20 is inserted into the mounting hole 12c of the blade sheath body 10, and the aforementioned mounting hole 12c is the positioning structure described above. Figure 3 and Figure 4 As shown, one end of the positioning block 20 abuts against the stop surface 16, and a portion protrudes into the socket hole 14. Here, the protruding portion is defined as a positioning part 22.

[0096] The locking device 30 provides a radial force to the tapered shank 201 inserted into the socket 14 of the blade sheath body 10, ensuring that the blade handle 200 is stably housed within the blade sheath 100. Please cooperate. Figure 2 , Figure 6 and Figure 7As shown, the locking device 30 includes a shaft tube 31, multiple steel balls 32, an unlocking member 33, a spring 34, a screw 35, a washer 36, a baffle 37, and multiple bolts 38. The shaft tube 31 is located in the socket hole 14, and its tube body has multiple side openings 31a, and a baffle 31b protruding towards the center on the inner tube wall. The steel balls 32 are respectively located in one of the side openings 31a. The unlocking member 33 passes through the shaft tube 31 and can reciprocate along the axis L. One end of the unlocking member 33 forms a tapered pushing part 33a. The steel balls 32 are kept in contact with each other; the spring 34 is sleeved on the unlocking member 33 and one end abuts against the retaining wall 31b; the screw 35 first passes through the washer 36 and then locks into a screw hole 33b of the unlocking member 33. At this point, the unlocking member 33, the screw 35 and the washer 36 can be regarded as a whole, and the other end of the spring 34 abuts against the washer 36; the retaining plate 37 has multiple through holes 37a. After the bolts 38 pass through the through holes 37a on the retaining plate 37 and the through holes 12d on the partition wall 12 of the blade body 10, they are locked into the corresponding screw holes (not shown) of the shaft tube 31.

[0097] When these bolts 38 are tightened, the shaft tube 31 and the baffle 37 will be forced to clamp against the two sides of the partition wall 12 respectively, and the baffle 37 will abut against the other end of the positioning block 20, ensuring that the positioning block 20 is stably inserted into the mounting hole 12c; the elasticity of the spring 34 will generate a pushing force on the unlocking member 33, causing the pushing part 33a to push these steel balls 32 outward. When the tapered shank 201 of the knife handle 200 is inserted into the sleeve hole 14, the pushing force of the spring 34 indirectly causes some of these steel balls 32 to fall into the annular groove 203, ensuring that the knife handle 200 will not easily disengage from the knife sleeve 100. The force of the aforementioned steel balls 32 acting on the annular groove 203 is the radial force defined in this invention. Conversely, if you wish to remove the handle 200, simply insert an auxiliary tool into the radial hole 12b of the sheath body 10, and the auxiliary tool pushes the screw 35 to move the unlocking member 33 and compress the spring 34, so that the steel balls 32 leave the annular groove 203, thus achieving the unlocking purpose.

[0098] In the above, when the taper shank 201 of the tool holder 200 is inserted into the socket hole 14, the positioning part 22 of the positioning block 20 will also simultaneously embed into the positioning groove 204 on the taper shank 201. Figure 7 (Refer to), so that the tool holder 200 cannot rotate relative to the tool sleeve body 10 with the axis L as the center. At this point, with the tool holder 200 fixed to the tool and the tool position point of the tool established, the tool changing mechanism can remove the correct tool holder 200 according to the machining program for subsequent machining operations.

[0099] Please cooperate again Figure 1 , Figure 8 and Figure 9 As shown, in this embodiment, the tapered shank 201 of the knife handle 200 is a polygonal cone, and its outer peripheral surface 201b is a non-circular peripheral surface formed by three connected arc surfaces. The tapered shank 201 forms an outward protrusion 201c at the connection point of adjacent arc surfaces. The socket 14 in this embodiment is a non-circular hole that mates with the tapered shank 201, and its hole wall has three inward protrusions 14a, with a recess 14b formed between adjacent inward protrusions 14a. When the tapered shank 201 of the knife handle 200 is inserted into the socket 14, each inward protrusion 14a of the socket 14 will abut against a corresponding arc surface of the tapered shank 201 and form a contact point T, thereby providing stable support for the knife handle 200. Each outward protrusion 201c of the tapered shank 201 is located in a corresponding recess 14b. Figure 8 The disclosure shows that there is a gap between the protrusion 201c and the recess 14b, which allows dust and debris adhering to the handle 200 to be discharged from there. Figure 9 This reveals that the positioning groove 204 is located on an arc surface, and the positioning block 20 is located in an inner protrusion 14a. It should be noted that the tapered shank of the knife handle can also be a cone, and the socket hole is a conical hole.

[0100] The above describes the structure of the tool holder according to a preferred embodiment of the present invention. The following describes the injection mold used to manufacture the tool holder body with a positioning structure (i.e., the mounting hole). This injection mold can adjust the position of some of its components to ensure that the positioning structure is located in a different position each time it is manufactured. That is, by setting the top and bottom positions of the tool holder body to be fixed, the positioning structure of the tool holder body is located in a different part within the mounting hole each time the position of some components of the injection mold is adjusted. Specific details are described below.

[0101] Please refer to Figure 10 and Figure 11 As shown, the injection mold 300 in this embodiment includes a molding base 310, a first slider 320, and a second slider 330. The molding base 310 is composed of a first half-mold 311 and a second half-mold 312 that can be engaged or opened. Please refer to... Figure 12As shown, the first mold half 311 has a parting surface 311a and an inner surface 311b recessed from the parting surface 311a, and the second mold half 312 has a parting surface 312a and an inner surface 312b recessed from the parting surface 312a. When the parting surface 311a of the first mold half 311 and the parting surface 312a of the second mold half 312 are engaged, the inner surface 311b of the first mold half 311 and the inner surface 312b of the second mold half 312 together form a cavity S. The molding base 310 is provided with a first opening 301 and a second opening 302 on both sides, respectively. The first opening 301 and the second opening 302 communicate with the cavity S, and a virtual baseline L1 is defined passing through the first opening 301, the cavity S and the second opening 302.

[0102] The first slider 320 and the second slider 330 are located on opposite sides of the molding base 310 and are both situated on the virtual baseline L1. The first slider 320 and the second slider 330 can not only be controlled to move back and forth relative to the molding base 310 along the baseline L1, but can also be adjusted and rotated around the baseline L1. The first slider 320 has a first end face 321 and a parting post 322 protruding from the first end face 321. The parting post 322 is located on the side offset from the baseline L1. The second slider 330 has a conical post 331, which has an outer peripheral surface 332 and a second end face 333. The outer peripheral surface 332 is a non-circular peripheral surface, and the second end face 333 protrudes a central post 334 and a plurality of extension posts 335.

[0103] like Figure 10 As shown, when the first half-mold 311 and the second half-mold 312 are closed, the first slider 320 and the second slider 330, which are defined on both sides of the molding mold base 310, are in an uninserted position P1. Figure 13 and Figure 14 As shown, when the first slider 320 and the second slider 330 are controlled to pass through the first opening 301 and the second opening 302 along the baseline L1 and extend into the cavity S, the first slider 320 and the second slider 330 in this state are located at an insertion position P2. At the same time, the parting post 322 of the first slider 320 and the cone post 331 of the second slider 330 are located in the cavity S, and the first end face 321 and the second end face 333 are separated by a distance W.

[0104] The injection mold 300 is in Figure 13 and Figure 14In the indicated state, an injection molding machine (not shown) is connected. The injection molding machine injects molten plastic into the injection mold 300 through an injection port 303, filling the cavity S. After the plastic cools and solidifies, the first slider 320 and the second slider 330 are controlled to retract along the baseline L1 to the uninserted position P1. At this time, the plastic originally filled between the outer peripheral surface of each slider 320 (330) and the inner surface 311b (312b) of each half mold, after cooling and solidification, forms the cylindrical structure of the die holder body 10. The plastic originally filled between the first end face 321 and the second end face 312b... The plastic between 33 forms the partition wall 12 of the blade sheath body 10, and the thickness of the partition wall 12 is equivalent to the spacing W. Furthermore, the space vacated by the parting post 322 of the first slider 320 not only forms the mounting hole 12c of the blade sheath body 10, but also forms the stop surface 16 on the wall of the socket hole 14. The space vacated by the central post 334 of the second slider 330 forms the axial hole 12a of the blade sheath body 10, the space vacated by its extension post 335 forms the through holes 12d of the blade sheath body 10, and the space vacated by its tapered post 331 forms the socket hole 14 of the blade sheath body 10. Then, by opening the first half-mold 311 and the second half-mold 312, the molded product taken out is the aforementioned blade sheath body 10.

[0105] From the above and in conjunction with Figure 9 As shown, in this embodiment, when the blade holder body 10 passes through its top end 10a and bottom end 10b along a virtual longitudinal line L2, its mounting hole 12c and the positioning block 20 are located on the left side. However, as described above, the injection mold of the present invention can achieve different orientations of the mounting hole within the socket hole by adjusting the positions of some components. Please refer to... Figure 15 As shown, with the mold-closing direction of the first half mold 311 and the second half mold 312 unchanged, the first slider 320 and the second slider 330 located at the uninserted position P1 are adjusted, that is, the first slider 320 and the second slider 330 are rotated 90 degrees around the baseline L1. Then, the same injection molding process described above is applied, and the position of the mounting hole 12c of the resulting tool holder body 10A will be as shown. Figure 16 As shown, it is located at the top. Similarly, by adjusting the first slider 320 and the second slider 330 and rotating them 90 degrees, the position of the mounting hole 12c of the resulting tool holder body 10B will be as shown. Figure 17 As shown on the right side; after adjusting the first slider 320 and the second slider 330 to rotate 90 degrees, the position of the mounting hole 12c of the resulting tool holder body 10C is as follows. Figure 18 The image shown is located below.

[0106] As can be seen from the above description, the first and second sliders of the injection mold of the present invention can be controlled to rotate between several fixed positions, and the positioning structure (i.e., the mounting hole) in the sleeve hole of the die holder body manufactured at different fixed positions is as follows: Figure 9 , Figures 16 to 18 As shown, the blade holders are positioned in different locations, allowing for the selection of appropriate blade sheath bodies for securing different blades. This ensures that the cutting point of each blade on the blade holder is effectively maintained in the designated position. It is worth noting that this invention can manufacture multiple blade sheath bodies using only a single mold, significantly reducing the cost of using multiple molds.

[0107] It should be noted that the above-mentioned fixed positions are based on a 90-degree rotation, but the rotation angle must be set according to actual needs. In addition, the rotation of the second slider does not have to be synchronized with the rotation of the first slider; it is also possible for the first slider to rotate while the second slider does not rotate.

[0108] The above description is only a preferred embodiment of the present invention. Any equivalent changes made by applying the present invention specification and the claims should be included within the patent scope of the present invention.

Claims

1. A tool holder suitable for a tool handle in a composite machining machine, wherein the tool handle has a tapered shank, the tapered shank has an end face and an outer peripheral surface, and the tool handle has a positioning groove located at the connection between the end face and the outer peripheral surface; characterized in that, This sheath includes: A knife sheath body has a socket and a virtual axis is defined through the center of the socket, the socket for the tapered shank of the knife handle to be inserted; A locking device for providing a radial force to the tapered shank inserted into the socket; A positioning block is fixed to the blade sheath body and has a positioning part protruding from the socket hole; wherein, when the cone shank is inserted into the socket hole, the positioning part of the positioning block is embedded in the positioning groove of the blade handle, and the blade handle cannot rotate relative to the blade sheath body with the axis as the center.

2. The tool holder for a composite machining machine as described in claim 1, characterized in that, The blade sheath body has an internal partition wall, and a socket hole is formed on one side of the partition wall. The partition wall has a mounting hole that connects the socket hole to the outside of the blade sheath body. The positioning block is inserted into the mounting hole.

3. The tool holder for a composite machining machine as described in claim 2, characterized in that, The connection between the wall of the socket and the wall of the mounting hole forms a stop surface. The locking device includes a stop plate. One end of the positioning block abuts against the stop surface. The stop plate is fixed to the partition wall and abuts against the other end of the positioning block.

4. The tool holder for a composite machining machine as described in claim 3, characterized in that, The tapered shank has a shaft hole recessed from the end face, and the wall of the shaft hole has a recessed annular groove. The locking device includes a shaft tube, multiple steel balls, an unlocking component, and a spring. The shaft tube is located in the sleeve hole and fixed to the partition wall. The shaft tube has multiple side openings, and the multiple steel balls are respectively located in a corresponding side opening. The unlocking component can be moved along the axis and passes through the shaft tube. The unlocking component has a pushing part, and the spring provides a pushing force to the unlocking component, causing the pushing part to push the multiple steel balls into the annular groove of the tapered shank.

5. The tool holder for a composite machining machine as described in claim 4, characterized in that, The locking device includes multiple bolts, the baffle has multiple through holes, and the partition wall of the blade sleeve body has multiple through holes. The multiple bolts pass through one of the through holes and one of the through holes respectively and are locked to the shaft tube.

6. The tool holder for a composite machining machine as described in any one of claims 1 to 5, characterized in that, The sleeve hole of the knife sheath body is a non-circular hole, and the outer circumferential surface of the cone shank of the knife handle is a non-circular circumferential surface. When the cone shank is inserted into the non-circular hole, there are at least two contact points between the non-circular circumferential surface of the cone shank and the hole wall of the non-circular hole.

7. The tool holder for a composite machining machine as described in claim 6, characterized in that, The non-circular hole of the knife sheath body has three inner protrusions, and a concave portion is formed between adjacent inner protrusions; the non-circular circumferential surface of the tapered shank of the knife handle is formed by three arc surfaces connected together, and an outer protrusion is formed at the connection point of adjacent arc surfaces; when the tapered shank is inserted into the non-circular hole, each inner protrusion abuts against a corresponding arc surface and forms a contact point, and each outer protrusion is located in a corresponding concave portion; the positioning groove of the knife handle is located on an arc surface, and the positioning block is located on an inner protrusion.

8. An injection mold for manufacturing a blade sheath body, the blade sheath body having an internal partition wall and a sleeve hole formed on one side of the partition wall, the partition wall having a mounting hole communicating with the sleeve hole and the outside of the blade sheath body; characterized in that, The injection mold includes: A molding base includes a first half mold and a second half mold, each half mold having a parting surface and an inner surface recessed from the parting surface; wherein when the parting surface of the first half mold is engaged with the parting surface of the second half mold, the inner surface of the first half mold and the inner surface of the second half mold together form a cavity. A first slider and a second slider are movable relative to the molding base from both sides along a virtual baseline between an insertion position and a non-insertion position. The first slider has a first end face and a parting post protruding from the first end face and offset from the baseline. The second slider has a cone post with a second end face. When the first half mold and the second half mold are closed and the first slider and the second slider are in the insertion position, the parting post and the cone post are located in the cavity, and the first end face and the second end face are separated by a gap. Therefore, when plastic is injected into the cavity of the molding base and cooled and shaped, the parting post is the mounting hole for forming the blade holder body, the cone post is the socket hole for forming the blade holder body, the distance between the first end face and the second end face is the partition for forming the blade holder body, and when the first slider and the second slider move to the non-inserted position and the first half mold and the second half mold are opened, the molded product taken out constitutes the blade holder body.

9. The injection mold as described in claim 8, characterized in that, The first slider, located in the uninserted position, is capable of rotating between several fixed positions centered on the baseline.

10. The injection mold as described in claim 9, characterized in that, The outer circumferential surface of the cone-shaped second slider is a non-circular circumferential surface. The second slider, located in the uninserted position, can be controlled to rotate synchronously with the first slider to a fixed position with the baseline as the center.

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