JP4733406B2 - Connection structure of rotating shaft - Google Patents

Description

  The present invention relates to a connecting structure for rotating shaft bodies such as gun drills and reamers used for deep hole cutting, for example, and more particularly to a connecting structure suitable for a rotating shaft body having a relatively small diameter.

  As a conventional connecting structure of this type of rotating shaft body, publicly known documents such as patent publications cannot be specifically cited. For example, a shank configured to connect a drill head of a gun drill and a shank, or to be divided into a plurality of parts. Conventionally, a connecting structure using screws is mainly used to connect the two.

  For example, the simplest structure as a screw connection structure when connecting a drill head and a shank is to form the connecting end of the drill head into a bolt-shaped male screw, and the connecting end of the shank into a nut. Thus, the nut-like connecting end portion of the shank is screwed into the bolt-like connecting end portion of the drill head and tightened.

  The screw connection structure is such that the drill head side of the gun drill is rotated clockwise in the same direction as the rotation direction with respect to the shank, so that both are tightened and connected together. In many cases, the head is excessively tightened against the shank, and when the drill head is replaced due to damage to the cutting edge of the drill head, the screw portion is not loosened, which makes it very difficult to remove the drill head.

  An object of the present invention is to provide a connecting structure of rotating shaft bodies that can easily and easily perform a connecting operation of both rotating shaft bodies to be connected and a disconnecting operation of both rotating shaft bodies connected to each other.

Means for solving the above problems will be described with reference numerals in the embodiments described later. The connecting structure of rotating shaft bodies according to the first aspect of the present invention is the rotating shaft bodies 1, 2 to be connected. Opening grooves 5 and 8 having a substantially V-shaped cross section along the axial direction are formed at least on the outer peripheral surface of the connecting end, and the connecting end of one rotary shaft 1 has a diameter smaller than that of the shaft 1. A shaft portion 1b is formed, and a connecting hole portion 9 is formed in the connecting end portion 2a of the other rotating shaft body 2 so as to fit in the connecting shaft portion 1b. A concave portion is formed on the outer peripheral surface of the connecting shaft portion 1b. A stepped portion 10 or a recessed stepped portion that forms a stepped portion 7 or a protruded stepped portion, and that is fitted into the recessed stepped portion 7 or the protruded stepped portion of the connecting shaft portion 1 b on the inner peripheral surface of the connecting hole portion 9. forming a, on the base end portion of the connecting shaft portion 1b and the front end portion of the connecting hole 9, and the connecting shaft portion 1b and the connecting hole 9 and the faucet fitting to and recessed step When a stepped portion is spigot fitting, for connection to attract both rotary shafts 1 and 2 by turning either one of both of the rotary shaft body 1 in a predetermined direction of rotation of the rotating shaft 1 The front end surface 14 of the concave step portion 7 or the convex step portion of the shaft portion 1b faces in the circumferential direction so as to be in pressure contact with the convex step portion 10 or the front end surface 15 of the concave step portion on the coupling hole 9 side, and in the axial direction. Engagement slope portions 11 and 12 that engage with each other are provided.

According to a second aspect of the present invention, in the connecting structure for rotating shaft bodies according to the first aspect, the engaging inclined surface portions 11 and 12 are formed along a helical winding centered on the central axis O of the rotating shaft bodies 1 and 2. It is characterized by.

The effect of the invention by the above-described solution means will be described with reference numerals in the embodiments described later. According to the invention according to claim 1, in order to connect both rotary shaft bodies 1 and 2, one rotation The connecting shaft portion 1b of the shaft body 1 is fitted into the connecting hole portion 9 in the connecting end portion 2a of the other rotating shaft body 2 by using the opening groove 8, and thus the both sides are fitted. When one of the rotary shafts 1 and 2 is rotated in the predetermined rotation direction of the rotary shafts 1 and 2, the circumference provided at the base end portion of the connecting shaft portion 1 b and the distal end portion of the connecting hole portion 9. Relative rotation of the rotating shafts 1 and 2 is prevented by the wedge engagement of the engaging slopes 11 and 12 that engage in the axial direction and the wedge engaging in the axial direction, and the concave step of the connecting shaft 1b. since the front end face 14 of the part 7 or convex stepped portion is pressed against the convex stepped portion 10 or the concave step portion front end face 15 in the connecting hole 9 side, rotating Body 2 is an axial movement of mutual blocking, whereby the two rotating shafts 1,2 are firmly integrally connected. Accordingly, both the rotary shaft bodies 1 and 2 can be easily and easily connected.

  Further, when the rotary shaft bodies 1 and 2 that are connected to each other as described above are disconnected, either one of the rotary shaft bodies 1 or 2 is turned in a direction opposite to the predetermined rotation direction of the rotary shaft bodies 1 and 2. Since the rotary shaft body 1 has only to be pulled out from the opening groove 8 to the side thereof, both rotary shaft bodies 1 and 2 can be easily and easily separated.

  As described above, only when both the rotary shaft bodies 1 and 2 are coaxially connected and rotated by the required driving means, the engaging slope 11 on the rotary shaft 1 side and the rotary shaft body 2 side are Since the engagement slope portions 12 are in pressure contact with each other, and the rotation drive is stopped by the driving means, the pressure contact state between the engagement slope portions 11 and the engagement slope portions 12 is released. The separation work of 2 is much simpler and easier than the conventional screw-type connection structure.

Further, according to the present invention, the concave step portion 7 or the convex step portion is formed on the outer peripheral surface of the connecting shaft portion 1 b, and the connecting shaft portion 1 b and the connecting hole portion 9 are formed on the inner peripheral surface of the connecting hole portion 9. By forming the convex step portion 10 or the concave step portion that fits the concave step portion 7 or the convex step portion of the connecting shaft portion 1b when the inner shaft is fitted with the spigot portion, the two rotary shaft bodies 1 and 2 are more It can be connected firmly and stably, and one rotary shaft 1 is a drill head 1 of a gun drill.
When the other rotary shaft 2 is a shank, when the drill head finishes penetrating the hole in the work material, the engagement slope 11 on the drill head side and the engagement slope 12 on the shank side disengage. Even if it will be in a state, since the concave step part 7 and the convex step part 10 are inlay-fitted, a drill head does not come out of a shank and it is safe.

  According to the second aspect of the present invention, the engaging slope portions 11 and 12 are almost in close contact with each other, and the tightening action between the rotating shaft body 1 and the rotating shaft body 2 can be sufficiently exerted. Can be linked accurately.

Hereinafter, an embodiment in which a connecting structure for rotating shaft bodies according to the present invention is implemented in a gun drill of a deep hole cutting tool will be described with reference to the drawings. FIG. 1 is a side view of the entire gun drill, and FIG.
Is a side view of the drill head of the gun drill, (b) is an end view of the drill head as viewed from the arrow a, (c) is a side view of the drill head from the arrow b, and (d) is a drill head from the arrow b. (E) is a sectional view of the knee line of (a), (a) of FIG. 3 is a perspective view of the drill head viewed from the opening groove side, and (b) is a drill head of the opening groove. (C) is the perspective view which looked at the connection end part side of the drill head from the opposite side to the opening groove. 4A is a side view of the gun drill shank viewed from the opening groove side, FIG. 4B is an end view of the shank viewed from the arrow E side, and FIG. 4C is a side view of the shank viewed from the arrow head. (d) is a sectional view taken along the tote line of (a), and (a) in FIG. 5 is a perspective view of the shank as viewed from the opening groove side, and (b) is a view of the shank from the side opposite to the opening groove side. FIG.

  1 to 5, 1 is a drill head (rotating shaft), 2 is a shank (rotating shaft), 3 is a screwdriver provided at the base end of the shank 2, and 4 is a coolant supply pipe on the shank 2 side. is there.

  This drill head 1 rotates in the right direction to make a hole in a work material. As shown in FIGS. 2 and 3, the head body 1a has a large diameter and is smaller in diameter than the head body 1a. And a connecting shaft portion 1b extending coaxially from the rear end of the head body portion 1a. The outer peripheral surfaces of the head body portion 1a and the connecting shaft portion 1b are substantially V-shaped in section along the axial direction thereof. An opening groove 5 is formed, and a coolant supply pipe 6 is formed along the central axis O from the rear end surface of the connecting shaft 1b to the head main body 1a. The front end of the pipe 6 is the head main body. It communicates with a coolant discharge port 24 opened at the tip end surface of the portion 1a. Further, a cemented carbide tip 25 and a guide pad 26 forming a cutting blade are fixed to the distal end side of the head main body 1a, and a concave step portion 7 is provided at the axial center of the outer peripheral surface of the connecting shaft 1b. It is installed.

  4 and 5, an opening groove 8 having a substantially V-shaped cross section similar to the opening groove 5 on the drill head 1 side is formed on the outer peripheral surface of the shank 2 along the axial direction. The connecting end 2a, which is the tip of the shank 2, is formed with a connecting hole 9 that fits into the connecting shaft 1b of the drill head 1 and this connecting hole 9 A convex step 10 is formed on the inner peripheral surface of the drill head 1 so as to fit into the concave step 7 of the drill head 1 when the drill head 1 and the shank 2 are connected. A hollow portion 13 for inserting a coolant supply pipe is formed along the central axis O inside the shank 2, and a coolant supply pipe 4 as schematically shown in FIG. 1 is inserted into the hollow portion 13.

  The base end portion of the connecting shaft portion 1b in the drill head 1 and the front end portion of the connecting hole portion 9 in the shank 2 (the front end portion of the connecting end portion 2a) are connected to the connecting shaft portion 1b and the connecting hole. When the portion 9 is fitted with the spigot and the concave step portion 7 and the convex step portion 10 are fitted with the spigot portion, they face each other in the circumferential direction, and either the drill head 1 or the shank 2 faces the predetermined rotation direction of the gun drill, that is, the right Engagement slopes 11 and 12 are provided for wedge engagement so as to attract both rotary shafts 1 and 2 by turning in the direction.

  As shown in FIGS. 2A, 2C, 3D, 3B, and 7, the engaging slope 11 on the drill head 1 side is the base end of the connecting shaft 1b. Specifically, the hook-shaped portion 1o formed at the end of the head main body portion 1a adjacent to the inner surface of the hook-shaped portion 1o has a helix angle of, for example, 45 ° around the central axis O of the drill head 1. It is formed along the winding.

  Further, as can be seen from FIGS. 4 (c), 4 (d), FIG. 5 and FIG. 7, the engaging slope portion 12 on the shank 2 side is formed on the front end side of the connecting hole 9 (the front end side of the shank 2). ) Formed on the inner side surface of the hook-shaped portion 2o that can be engaged with the hook-shaped portion 1o on the drill head 1 side. More specifically, as with the slope portion 11, the center axis O of the shank 2 (which is the center axis common to the center axis of the head main body 1a) is centered along a spiral wire having a twist angle of 45 °. Is formed.

The opening groove 5 formed on the drill head 1 side and the opening groove 8 formed on the shank 2 side have a function of discharging cutting waste, respectively, and in connecting the drill head 1 and the shank 2 in FIG. The connecting shaft 1b of the drill head 1 is connected to the shank 2 in a state where the connecting shaft 1b of the drill head 1 is arranged in parallel to the side of the connecting end 2a of the shank 2 as shown in FIG. It has a function to insert into the hole 9. The opening grooves 5 and 8 are formed so that the opening angle θ from the central axis O of each of the drill head 1 and the shank 2 is about 110 °.

  Thus, in order to insert the connecting shaft portion 1b of the drill head 1 into the connecting hole portion 9 of the shank 2, as can be seen from FIGS. When the opening width is W and the minor axis of the connecting shaft portion 1b is N, it is necessary that W> N. Further, the opening angle θ of the opening grooves 5 and 8 may be in the range of 90 ° to 150 °.

In order to connect the connecting shaft 1b of the drill head 1 to the tip 2a (connecting end) of the shank 2 configured as described above, the drill head 1 is brought in parallel to the tip 2a of the shank 2. As shown in FIG. 6 (a), the drill head in the direction indicated by the arrow in the drawing with the minor axis N side of the connecting shaft portion 1b of the drill head 1 facing the opening groove 8 of the shank 2 1 is made parallel to the shank 2, the connecting shaft portion 1 b of the drill head 1 is inserted into the connecting hole portion 9 of the shank tip 2 a, and the connecting shaft portion 1 b is fitted into the connecting hole portion 9 by inlay fitting. While the drill head 1 is rotated in the direction of the arrow shown in FIG. 5B, the convex step portion 10 of the connecting hole portion 9 is in-fitted to the concave step portion 7 of the connecting shaft portion 1b, and the drill engaging the hook-like portion 1o head 1 side is engaged with the hook-like portion 2o of the shank 2 side Was how slope portions 11 and 12 engaged wedge.

  As described above, the connecting shaft portion 1b of the drill head 1 fits into the connecting hole portion 9 of the shank tip 2a, and the concave step portion 7 of the connecting shaft portion 1b and the convex step portion of the connecting hole portion 9 are provided. The engaging slope portion formed on the inner surface of the hook-shaped portion 1o while the hook-shaped portion 1o on the drill head 1 side and the hook-shaped portion 2o on the shank 2 side are engaged with each other when the 10 is in-slot fitted. 11 and the engaging slope portion 12 formed on the inner side surface of the hook-like portion 2o are in a state of facing each other in the circumferential direction. In this state, either the drill head 1 or the shank 2, in this case, the shank 2 By rotating the side to the right, which is the predetermined direction of rotation of the gun drill, as shown in FIG. 7, the engagement slope portion 12 on the shank 2 side and the engagement slope portion 11 on the drill head 1 side are wedge-engaged. Both rotary shafts 1, 2 are attracted in the opposite direction, Drill head 1 is coupled coaxially integrally on the tip portion 2a of the shank 2 by Les.

  6 (a) to 6 (c), α indicates the formation range of the engaging slope portion 11 formed on the drill head 1 side, and β indicates the engaging slope portion formed on the shank 2 side. 12 shows the formation range. In FIG. 6 (c), α and β are in an overlapped state. Therefore, the engagement slope 11 on the drill head 1 side and the engagement slope 12 on the shank 2 side are both rotating shaft bodies. A state in which wedges 1 and 2 are engaged so as to attract each other is shown.

  As described above, when both the engaging slopes 11 and 12 are wedge-engaged, the relative rotation of the rotating shaft bodies 1 and 2 is prevented and the axial movement between the rotating shaft bodies 1 and 2 is also prevented. Therefore, the two rotating shaft bodies 1 and 2 are connected coaxially and integrally, but in this embodiment, as can be seen from FIG. Since the concave step portion 7 of the portion 1b and the convex step portion 10 of the connecting hole portion 9 are inlay-fitted, the two rotary shaft bodies 1 and 2 are attracted in the opposite direction to the connecting shaft portion 1b. The front end surface 14 of a certain concave step portion 7 is in pressure contact with the front end surface 15 of the convex step portion 10 on the connecting hole 9 side of the shank 2, and the rear end surface 16 of the connecting shaft portion 1 b is connected to the shank 2. Press contact with the back end surface 17 of the hole 9 for the drill, thereby making the drill head 11 more firm to the tip 2a of the shank 2 Is the body connected.

In this manner, with the connecting shaft portion 1b of the drill head 1 integrally connected to the distal end portion 2a of the shank 2, the drill head 1 is rotated by driving the screwdriver 3 at the base end portion of the shank 2 to the right. Drilling is performed by rotating integrally with the shank 2. Further, by connecting the drill head 1 and the shank 2, the coolant supply pipe 4 fitted into the hollow portion 13 of the shank 2 and the coolant supply pipe 6 of the drill head 1 are connected in communication. In this case, the rear end face 16 of the connecting shaft portion 1b.
However, since the back end surface 17 of the connecting hole 9 of the shank 2 is in pressure contact, the sealing action by the pressure contact causes leakage of coolant from the connecting portion between the coolant supply pipe 6 and the coolant supply pipe insertion hollow portion 13. Can be prevented.

  In order to remove the drill head 1 connected to the tip 1a of the shank 2 as described above, the drill head 1 is rotated leftward, which is the direction opposite to the predetermined rotation direction of the gun drill, as shown in FIG. Since the drill head 1 has only to be pulled out from the opening groove 8 to the side thereof from the state shown in FIG.

  In this gun drill, as described above, the drill head 1 is engaged only when the drill head 1 is coaxially connected to the distal end portion 1 a of the shank 2 and is rotated by the driver 3 at the proximal end portion of the shank 2. When the slope 11 and the engagement slope 12 of the shank 2 are wedge-engaged and pressed against each other, and the rotational drive by the driver 3 is stopped, the engagement slope 11 and the engagement slope 12 Since the pressure contact state is released, the removal operation of the drill head 1 is much simpler and easier than the conventional screw type connection structure or key type connection structure.

  Also, as described with reference to FIGS. 6A to 6C, the mounting operation of the drill head 1 when connecting the drill head 1 to the shank 2 can be performed simply and easily as described above with reference to FIGS. it can.

  In the embodiment described above, the engagement slope portion 11 on the drill head 1 side and the engagement slope portion 12 on the shank 2 side are along the spiral winding centering on the central axis O of the drill head 1 and the shank 2. Although it forms, the engagement slope parts 11 and 12 may be formed in a linear slope. However, by making the engaging slope portions 11 and 12 along the helical winding as in this embodiment, both the engaging slope portions 11 and 12 are almost in close contact with each other, and the drill head 1 and the shank 2 are in close contact with each other. Can be sufficiently exerted, and both can be accurately connected.

  Moreover, in the above-mentioned embodiment, since the connection structure of this invention is implemented in the gun drill of the deep hole cutting tool, although the opening grooves 5 and 8 are formed over the full length of the drill head 1 and the shank 2, In the case of a simple rotating shaft body connecting structure, the opening groove may be formed only at the connecting end of the rotating shaft body.

  Further, in the above-described embodiment, the recessed step portion 7 is provided around the outer peripheral surface of the connecting shaft portion 1b, and the inner peripheral surface of the connecting hole portion 9 is provided with an inlay relative to the recessed step portion 7 on the connecting shaft portion 1b side. When the projecting step portion 10 to be fitted is formed and the drill head 1 and the shank 2 are connected, the connecting shaft portion 1b and the connecting hole portion 9 are inlay-fitted, and the recessed step portion 7 and the projecting step portion. 10 is adapted to be inlay-fitted, but due to the wedge engagement of the engaging slopes 11 and 12, relative rotation of both rotary shafts 1 and 2 is prevented, and at the same time the rotary shafts 1 and 2 are engaged. Since the mutual axial movement is prevented, the concave step 7 and the convex step 10 are not necessarily required. However, by providing the concave step portion 7 and the convex step portion 10 as described above, the drill head 1 and the shank 2 can be more firmly and stably connected to each other. The drill head 1 and the shank 2 may rotate in the opposite directions when the holes have been penetrated, and the engagement slope 11 on the drill head 1 side and the engagement slope 12 on the shank side are disengaged. However, since the recessed step portion 7 and the protruding step portion 10 are inlay-fitted, the drill head 1 does not come out of the shank 2 and is safe. In addition, the recessed part 7 and the convex step part 10 may be formed not only in one place but in two places or three places.

It is a side view of the whole gun drill. (a) is a side view showing the drill head of a gun drill, (b) is an end view of the drill head viewed from the arrow a, (c) is a side view of the drill head viewed from the arrow b, and (d) is a drill head. A side view seen from the arrow B, (e) is a sectional view of the knee line (a). (a) is a perspective view of the drill head as viewed from the side of the opening groove, (b) is a perspective view of the drill head as viewed from the side opposite to the opening groove, and (c) is a connection end side of the drill head opposite to the opening groove. It is the perspective view seen from the side. (a) is a side view of the gun drill shank viewed from the opening groove side, (b) is an end view of the shank viewed from the arrow e side, (c) is a side view of the shank viewed from the arrow head, and (d) is a side view of the shank. It is a sectional view taken along the tote line (a). (a) is the perspective view which looked at the shank from the opening groove side, (b) is the perspective view which looked at the shank from the opposite side to the opening groove side. It is explanatory drawing explaining the state which connects a drill head to a shank front-end | tip part. It is a partial cross section side view in the state where the drill head was connected to the shank tip.

Explanation of symbols

1 Drill head (rotating shaft)
DESCRIPTION OF SYMBOLS 1a Head main-body part 1b Connecting shaft part 1o Hook-shaped part 2 on a drill head side 2 Shank (rotary shaft)
2a Shank tip (connecting end)
2o Shank-side hook-shaped portion 5 Open groove 7 Concave step portion 8 Open groove 9 Connecting hole portion 10 Convex step portion 11 Engagement slope portion 12 on the drill head side Engagement slope portion on the shank side

Claims (2)

An opening groove having a substantially V-shaped cross section is formed in the axial direction on at least the outer peripheral surface of each of the rotating shaft bodies to be connected, and the diameter of the rotating end of the one rotating shaft body is larger than that of the shaft body. A small connecting shaft portion is formed, and a connecting hole portion is formed in the connecting end portion of the other rotating shaft body so as to fit into the connecting shaft portion, and a concave step portion is formed on the outer peripheral surface of the connecting shaft portion. Alternatively, a convex stepped portion is formed, and a convex stepped portion or a concave stepped portion that is inlay-fitted to the concave stepped portion of the connecting shaft portion or the convex stepped portion is formed on the inner peripheral surface of the connecting hole portion. When the connecting shaft portion and the connecting hole portion are inlay-fitted and the concave step portion and the convex step portion are inlay-fitted to the base end portion of the portion and the distal end portion of the connecting hole portion, the front end face bore side for connection of the concave stepped portion or the convex stepped portion of the connecting shaft portion so as to attract the rotating shafts by turning either one in a predetermined direction of rotation of the rotating shaft of the rotary shaft body Connection structure that convex stepped portion or the recessed step circumferentially facing to and axially formed by providing an engagement inclined surface portion for wedging engagement with one another rotary shaft so as to press the front end surface of the. Connecting structure of the rotary shaft of each engagement inclined surface portion according to claim 1 obtained by forming along the helical line shall be the center axis line of the rotation shaft.

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