SI25251A - Quick-release chuck - Google Patents

Abstract

A self-locking quick-locking drill head comprising a cylindrical body having at least one bore for receiving a support pin or clamp holder in the working device and, on the other end, an open cavity for receiving clamping jaws, clamping jaws in which it is mounted and clamping a tool in the form of a drill and a rotating body surrounding the cylindrical body and the clamping jaws, wherein the clamping jaw is formed as a cylindrical section whose top extends over the center of the cylinder with an eccentric hole located in the region of the top outside the center of the cylinder, with an oblique teeth on the circular casing, and a rotating toothing arranged at the top of the cylindrical section along the entire height of the clamping jaw, wherein the clamping jaw is via a eccentric bore rotatably mounted on the cavity radially and with the longitudinal axis of the drill head parallel to the guide pin.

Description

SELF-INTRODUCTORY FAST VPNAL VERTICAL HEAD The subject of the invention

The object of the invention is a self-locking fast-clamping drill head comprising a cylindrical body having a bore at its rear end for receiving a support pin or clamping device into the working device and is open at its front end for receiving clamping jaws and a rotating body surrounding cylindrical body and clamping jaws.

Technical problem

The technical problem is to design a self-fastening quick-clamping head with clamping jaws, which will allow quick and easy clamping and drilling of the drill with a relatively small force without any use of the additional tool, even during operation of the working device, and at the same time ensuring sufficient force of clamping of the working tool , this is a drill without causing deformation on the drill stem, or that the deformations are minimal, which will significantly increase the life of both the drill and the clamping head. At the same time, the design of the clamping head should be simple, from a small number of components and economically justified.

State of the art

The clamping drill heads known from the state of the art have a body of a head in which most often three clamping jaws are arranged, among which a working tool in the form of a drill is clamped. The clamping jaws are elongated cylindrical shapes and are arranged in the body of the head in a uniform manner at spaced intervals and inclined with respect to the longitudinal axis of the drill head so that the inner ends of the jaw are more distant than the longitudinal axis of the drill head as the outer ends. The jaws have a threaded toothing in the part of their length, which is fitted with a threaded ring, through which the jaws move in the longitudinal direction of the axis of the clamping head. The rotation of the threaded ring causes the clamping jaws to move in the longitudinal direction of the main axis so that the brightness changes between the front ends of the jaw. When clamping the drill, the clamping jaws combine and screw the drill with the outer ends. Each outer end of the jaw is tanned in the shape of a wedge, the tip of which extends in the direction of the longitudinal axis of the drill head and along the drill. Using a wedge, the jaw buckles the body of the drill either point or line, depending on the design of the jaw, and, together with the remaining two jaws, creates a force of clamping. The clamping force must be sufficiently large to prevent rotation of the drill. Due to the large clamping force and the wedge shape of the jaw, there are often damages and deformations of the stem of the drill, which can cause slipping of the stems in the drill head, the elimination from the center and the accuracy of the circular run, and thus inaccurate processing. In the worst case, drill bit can also be released from the drill bit during operation. In this case, the axial mounting is again ensured by increasing the clamping force, thereby increasing the risk of damage. Increasing the clamping force also has negative consequences when drilling the drill from the drill bit, as this increases the force required to drill the drill from the head. This, in turn, also affects the time required to replace the drill. Such a drill rigging design also requires a very precise radial arrangement of the clamping jaws and their angular movement relative to the longitudinal axis of the drill head. Otherwise, the drill bit is not centered and the accuracy of the circular run is dissatisfied.

In the second design of the clamping head, the clamping jaws are designed as trimmed conical cuts that are connected either with a conical threaded ring or a special threaded screw. The latter is screwed in with a rotating housing. With the aid of a rotating housing and a screw, the clamping jaws move in parallel and in the direction of the longitudinal axis of the drill head. When moving in the longitudinal direction, the jaw with its outer surface slides along the inner surface of the conical shaped head housing. As a consequence, the jaw brightness, when they move in the direction of the outlet from the drill head, decreases and vice versa, when the jaws move towards the inside of the drill head, the brightness increases. At that time, the drill head can receive a larger drill or release one that is clamped in the drill bit. These types of drill heads, as well, usually have three clamping jaws, among which a sufficiently large clamping force is attached to the drill bit. To ensure that the drill bit is centered in the drill bit, t. im. the precision of the circular run requires extraordinary precision production of all the components which must be completely coaxial. The clamping force must be relatively large to prevent rotation of the drill. Consequently, damage to the stem of the drill can occur.

Solving the technical problem

Said technical problem is solved by means of a self-locking fastening drill head comprising a cylindrical body having at its one end a bore for receiving a support spindle or clamp holder in the working device, and an open cavity for receiving clamping jaws, clamping jaws on the second front opening , in which the drill tool is mounted and fixed, and a rotatable body surrounding the cylindrical body and the clamping jaws, wherein the clamping jaw is formed as a cylindrical section whose tip extends over the center of the cylinder with an eccentric hole located in a region of the top outside the center of the cylinder, with an oblique tooth on the circular casing, and a rotating toothing arranged at the top of the cylindrical section along the entire height of the clamping jaw, wherein the clamping jaw is via a eccentric bore rotatably mounted on the cavity radially and with the longitudinal axis of the drill head a parallel mounting guide shaft.

The clamping jaws are in gear gear with a swivel housing, the rotation of which causes the clamping jaws to rotate about the guide silo, whereby the clamping jaws are spaced apart to accommodate the working tool.

The clamping jaws are in conjunction with the rotating body through a pre-stressed bending spiral spring arranged in the cylindrical body and the force of the clamping jaw in a closed position. The bending spiral spring is attached to the cylindrical body with one end, with the other end being attached to the rotating body. When a drill is mounted in the drill bit head, the bending spiral spring closes the clamping jaws, which, with the help of an oblique tooth located on the circular sheath of the jaw, hold the drill bit. The drilling force acting in the opposite direction of the drilling acts on the oblique toothing of the clamping jaws and closes the clamping jaws. Consequently, the clamping force of the drill is increased in the clamping jaws, and the force of the springs can be reduced. Due to the multi-point attachment of the stem of the drill in the jaws, which is a consequence of the oblique tooth, the deformations of the stem of the drill are smaller.

The drill head has a centrally arranged magnet in the front surface, which prevents the drill failure from drilling head during its replacement when the drill jaws do not adhere to it. At the same time it also helps in centering the drill.

Due to the smaller force required, a smaller force is required for drilling the drill bit from the drilling head, which leads to easier handling. This design of clamping jaws and drill heads makes it relatively easy to carry with a small number of components.

The essential advantage of the drill head according to the invention is that its design allows the drill to be changed during the operation of the working machine, which significantly contributes to improving work efficiency. The required force required to open the clamping jaws is small and can be achieved by hand-pressing the rotatable housing. A saw inserted between the open jaws grabs the magnet and holds it until it clicks the clamping jaws. The magnet also prevents the failure of the drill from the clamping jaws in the event of a slip when the clamping jaws are already open. At the same time, the magnitude of the magnet is only so that the drill bit can be easily manually removed from the clamping jaws. Since the magnet and thus the drill bit is centered, the rotational speeds are low and do not pose a danger to the user.

Due to the eccentric clamping of the clamping jaws, the radius of the casing of the jaw on which the oblique tooth is positioned increases with an angle. This also enables the mounting of drills of different diameters or different sizes. This allows the use of one drill head for multiple drill sizes.

An additional advantage of the drill head according to the invention is the self-centering of the drill during clamping, which is the result of three cylindrical jaws with varying radius of oblique tooth.

The drill head according to the invention is intended for use in hand drills and drill rigs, for mounting on clamps for clamps or directly on the spindle of the machine.

The invention will be described in more detail on the basis of the embodiment and illustrations shown

Fig. 1 Self-fastening fastening drill head according to the invention, longitudinal cross-section Fig. 2 Self-fastening fastening drill bit according to the invention, front view

The self-locking fast-chuck drilling head 1 comprises a cylindrical body 10 having, at one end, a central hole 11 for receiving a support pin or clamp holder in the working device and having an open cavity at the front end which accommodates three prismatic clamping jaws 20 in the form a cylindrical section whose top 25 extends over the center of the cylinder, three sails 30 which are radially arranged within the front cavity 12 of the cylindrical body 10 at equal intervals and on which the clamping jaws 20 are rotatably rotatably arranged, a rotatable body 40 surrounding the cylindrical body 10 and of the clamping jaw 20, wherein the rotatable housing with clamping jaws 20 is connected via a gear pair 23, 42 and is connected to the cylindrical body 10 by an elastic element in the form of a bending spiral spring 50 which returns the clamping jaws 20 to the starting position, the closed position, and the lid 60 which closes the open cavity of the cylindrical body and thus also the front part of the drill head 1.

The cylindrical body 10 has, at one end, a central hole 11 for receiving a support pin or mounting bracket in the working device and an open cavity 12 at the front end to accommodate three prismatic clamping jaws 20. An open cavity 12 in the embodiment encloses three attachment attachments 13 for mounting of the lid 60 which are arranged on the circumferential part of the cylindrical body 10. In the embodiment, the fixing of the lid 60 is carried out by a screw connection. In the region of the rear part of the cylindrical body 10, a peripheral groove 15 is arranged along the periphery, in which the elastic element is arranged in the form of a prestressed bending spiral spring 50, which will be described in more detail below. In the face of the cylindrical body 10, which essentially the base surface of the cavity 12 and at the same time restricts the insertion of the drill into the clamping jaws, three screw holes 14 are arranged radially at the same intervals, each receiving the leading sock 30, more specifically the thread end of the respective guiding beam 30. At the free end of the socket 30 extending into the open cavity 12, the clamping jaw 20 is rotatably mounted.

The clamping jaw 20 is a prism made in the form of a cylindrical section whose tip 25 extends over the center of the cylinder. The clamping jaw 20 has an eccentric bore 21 through the center of the cylinder, through which the clamping jaw 20 is rotatably mounted on the guide shaft 30 and swinging around its axis. On the circular part of the casing of the clamping jaw 20, an oblique tooth 22 is arranged, with which the respective jaw 20 together with the other two clamping jaws 20 engages the tool in the form of a drill, more specifically the drill bit. The inclined teeth 22 extending over the entire annular circumferential portion has an inclination greater than 0 ° with respect to the longitudinal axis and less than 45 °, more particularly between 5 ° and 20 °, more particularly between 6 ° and 15 °, and depends on the area of the drill size for which the respective drill head is used. The shape of the teeth in the oblique tooth is pointed. The tooth inclination and the shape of the teeth achieve a large clamping force, which operates on a relatively large length of the drill bit, as the drill stem is clamped between the clamping jaws over their entire height. Due to the distortion of the bore 21 and thus the displacement of the oscillation axis of the clamping jaw 20, the radial distance of the oblique tooth 22 from the oscillating axis with the angle changes, which allows the mounting of the drills of a certain dimension area, not just one dimension of the drill. Each clamping jaw 20 is arranged on the guide shaft 30 so that the clamping jaw 20 rotates in the direction of the smaller radius when opening.

On the opposite side of the circular jacket of the clamping jaw 20, in the region of the top, the rotational toothing 23 extends along the entire height of the clamping jaw 20, preferably in the form of two teeth, which engage with the sole rotational toothing 42 on the inner periphery of the rotatable housing 40, which will be described below.

The rotatable housing 40 encloses the cylindrical body 10 and the clamping jaw 20 and is also connected to them simultaneously, and, in the embodiment, can be dismantled. With the cylindrical body 10, the rotatable housing 40 is connected via an elastic element in the form of a pre-stressed bending spiral spring 50, which is arranged in the winding groove 15 of the cylindrical body in the circumferential groove 15. The spiral spring 50 is attached at one end to the cylindrical body 40 with the other end on a rotatable housing 10. The clamping jaws 20 and the swivel housing 40 are in the mutual gear pin 23, 42. On the inner circumference of the rotatable housing 40, the cycloid grooves 43 are formed in the region of the clamping jaws 20 in which the clamping jaws 20 are removed when opening.

The rotation of the rotatable housing 40 due to the permanent gearing 42, 23 causes the rotation of the respective clamping jaw 20, with the clamping jaws 20 spacing apart. In order to ensure a sufficient rotation of the respective clamping jaw 20, there are arranged cycloid grooves in the inner periphery of the rotatable housing 40 in which the respective clamping jaw 20 is partially withdrawn in the open position when the jaws rotate. The rotating housing 40 rotates bendably to the spiral spring 50 which, stopping load, i.e. when releasing the rotatable housing 40, returns to its initial position. Together with the spring 50, the rotatable housing 40 and the rotary jaws 20 are returned to the starting position. In the case where the drill bit or drill bit is drilled in the drill head, it prevents the returning of the clamping jaws and the bending spring into the starting position. The clamping jaws clamp the stem of the drill with the bending force of the bending spring 50.

An embodiment of the drill head has a central magnet 16 in the front surface of the cylindrical body 10 acting on the inserted drill bit and prevents its failure from the drill head at a time when the drill bit is not clamped in the clamping jaws 20.

The cover 60 which closes the drill head 1 from the front side and thereby also the rotatable housing 40 together with the cylindrical body 10 and the clamping jaws 20 has a central opening 61 for clamping and drilling the drill. The central aperture 61 is exerted inwardly against the inside by means of a large filing, which allows the leaks to flow out, which can accumulate in the drill head itself. The cover 60 has a surface facing the interior of the drill head, the guiding bores 62 for positioning the guide sockets 30. The inner surface of the lid is also limited in the axial direction by the clamping jaws 20 which, therefore, in the immediate vicinity of the borehole 21naslon 24 with which they attach to the inner the surface of the lid 60. The lid 60 is, in the embodiment, screw-fastened to the respective lug 13.

It is understandable that a field expert may also perform different embodiments without circumventing the essence of the invention.

Claims (8)

Patent claims A self-locking fastening drilling head comprising a cylindrical body having a bore at one end for receiving a bearing mandrel or a clamping device into the working device and opening a cavity (12) for receiving clamping jaws at the front end, a clamping jaw (20) into which the drill tool is mounted and clamped, and a rotatable housing (40) surrounding the cylindrical body and the clamping jaws, characterized in that the clamping jaw (20) is constructed as a cylindrical section, the top (25) extends over the center of the cylinder, with an eccentric bore (21) located in the region of the top (25) outside the center of the cylinder, with an oblique tooth (22) on the circular sheath portion, and a rotating toothing (23) (25) of the cylindrical section along the entire height of the clamping jaw, wherein the clamping jaw (20) is rotatably mounted on a cavity (12) in a cavity (12) radially and with the longitudinal axis of the drill head in parallel with the guide cock (30). 2. Self-fastening fastening drill bit according to claim 1, characterized in that it comprises three clamping jaws (20) and three guide sockets (30) radially arranged in equal intervals and arranged on each guide shaft (30) one clamping jaw (20). Self-locking fastening drill bit according to claim 1, characterized in that the oblique tooth (22) has an inclination greater than 0 ° and less than 45 ° with respect to the longitudinal axis of the drill head, more particularly between 5 ° and 20 °, more particularly between 6 ° and 15 °. Self-locking fastening drill bit according to claim 1, characterized in that the rotation gear (23) engages with a toothed rack (42) arranged on the inner periphery of the rotatable housing (40) so that the rotation of the rotatable housing (40) causes rotation of the clamping jaws (20) around the guiding beam (30) and their spacing. A self-locking fastening drill bit according to claim 4, characterized in that the cycloidal grooves (43) are made on the inner periphery of the clamping jaws (20) in which the rotatable housing (40) has a clamping jaw (20 ). A self-locking fastening drill bit according to claim 1, characterized in that the cylindrical body (10) has a circumferential groove (15) in which an elastic element is in the form of a bending spiral spring (50) which is connected with one free end with a cylindrical body (10) and a second free end with a rotatable housing (40), to return the clamping jaws (20) to the starting position. Self-locking fastening drill bit according to claim 1, characterized in that the cylindrical body (10) has a centered magnet (16) in the front surface. Self-fastening fastening drill bit according to any of the preceding claims, characterized in that the lid (60) closes the cylindrical body.