JP3474503B2 - Tightening structure of rotary tool - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool, and more particularly, to a rotary tool in which a member disposed around a rotary shaft is concentric with the rotary shaft. Tightening technology. 2. Description of the Related Art Conventionally, as a rotary tool, for example, a woodworking cylinder as shown in FIGS. 6 and 7 has been known. Here, FIG. 6 is a side view of a conventional woodworking cylinder, and FIG. 7 is a front view of FIG. Each of FIGS. 6 and 7 partially shows a cross section. As shown in FIG. 6, a cylindrical plane body 110 having a cylindrical shape is fixed via a bush 120 around the rotation shaft 101 (indicated by a two-dot chain line). The plane body 110 is configured to rotate in the direction of arrow 150 in FIG. At four places on the outer periphery of the plane body 110, there are blade grooves 111a-11.
1d, and a blade assembly 112a-1 in which a blade 113 and a backrest 114 are integrally combined in the blade groove, respectively.
12d is installed. Also, for example, the knife assembly 11
2a indicates a plurality of fastening bolts 115 (arrows 130 in the drawing).
Side wall 110 of the plane body 110 by the clamping force
a. [0003] As shown in FIGS.
0 is a flange 120a that partially overlaps the plane body 110
The flange 120a is inserted into both ends of the plane body 110 in a state in which the flanges 120a are in contact with each other. And the bush 120 is
It is fixed to the plane body 110 by four fixing bolts 116 at the position of the flange 120a. A sealed space 121 is formed in a circumferential direction between the outer peripheral surface of the bush 120 and the inner peripheral surface 110b of the plane body 110,
A pressure medium (eg, grease) is applied to the grease nipple 12.
3, the space 121 is maintained in a pressurized state. As a result, the bush 120 is pressed in the direction of arrow 134 in the figure, and the inner diameter 120b is reduced.
Therefore, the inner diameter 120b of the bush 120 is
Of the rotating shaft 101
Concentricity of the plane body 110 with respect to the center line (centering function). By using this centering function, the cutter grooves 111a to 111d are accurately formed on the outer periphery of the plane cylinder main body 110, and when a cutter assembly is installed in each cutter groove, the cutter 113 with respect to the rotating shaft 101 The concentricity of the cutting edge position can be improved. However, in the above-mentioned conventional woodworking cylinder, for example, when the blade assembly 112a is tightened by a tightening bolt 115 (an external force is applied), this figure (FIG. Due to the tightening force (in the direction of arrow 130 in FIG. 6), the opening of the blade groove 111a is elastically deformed in the direction in which it is further opened. Then, the blade edge of the blade 113 is displaced in the direction of arrow 132 in FIG. 6 with the elastic deformation of the side wall 110a. Therefore, when a plurality of tightening bolts 115 are used for one blade assembly 112a, the plane cylinder body 11
0, the concentricity of the cutting edge position of the cutting tool 113 with respect to the rotating shaft 101 is reduced due to unevenness of the rigidity of each part, variation in the tightening force, time lag in the tightening, and the like. In addition, the rotating shaft 1
01, the concentricity of the cutting edge position of the cutting tool 113 is
It has been found that it occurs not only for each blade assembly but also between the blade assemblies. In a woodworking cylinder, the decrease in concentricity between the blade assemblies deteriorates the peripheral runout accuracy of the cutting edge. Also, when the blade assembly 112a is repeatedly attached and detached from the blade groove 111a, the fixing bolt 116
There is a small play between the bolt and the bolt mounting hole, so that a relative displacement occurs between the plane cylinder main body 110 and the bush 120, and particularly, a radial displacement accumulates so that the blade 113 with respect to the rotating shaft 101 is displaced. It has been found that the concentricity of the cutting edge position is further reduced. Therefore, even when the blade assembly 112a-112d is tightened by the tightening bolt 115, the rotating shaft 10
1 other members (plane cylinder body 110, bush 120
Etc.) can be maintained, the blade 113
The present inventors have a great advantage that the concentricity of the cutting edge position of the cutting edge (outer edge runout accuracy) can be maintained and the machining accuracy of the work can be maintained. did. As a result, we have:
If the mounting structure of the bush 120 to the plane cylinder body 110 is improved, the plane cylinder body 110 and the bush 120 can be concentrically tightened with respect to the rotation shaft 101 even when the tightening bolt 115 is tightened. It has been found that the concentricity of the plane body 110 and the bush 120 with respect to the shaft 101 can be maintained. According to the present invention, even when an external force acts on a member provided around the shaft of the rotary shaft, the member can be concentrically tightened with respect to the rotary shaft, and the member is higher than the rotary shaft. An object of the present invention is to provide a tightening structure of a rotary tool that can maintain concentricity. [0007] In order to solve the above-mentioned problems, a tightening structure for a rotary tool according to the present invention is configured as described in claim 1. Here, the terms described in claim 1 and the detailed description of the invention are interpreted as follows. (1) In addition to cutting tools (for example, woodworking cylinders) that perform cutting by rotating the processing blade,
Various processing (for example,
Polishing, cutting, etc.). According to the tightening structure of the rotary tool according to the first aspect, the fixing member for fixing the relative position of the outer peripheral member to the inner peripheral member is provided at a specific position on the inner and outer peripheral members, so that the outer peripheral member is provided. When an external force acts on the outer peripheral member, radial displacement of the outer peripheral member with respect to the rotating shaft can be suppressed within a predetermined value. Therefore, the outer peripheral member can be tightened concentrically with respect to the rotation axis, and high concentricity can be maintained with respect to the rotation axis. Further , according to the present invention , in a state where the flange portion of the inner peripheral member and the outer peripheral member are overlapped with each other, a pin is inserted into the flange portion of the inner peripheral member and the outer peripheral member without any gap to fix both members. Therefore, both members can be firmly fixed by a relatively simple configuration of the fixing member. According to the present invention, even when the mounting force of the mounting means acts on the outer peripheral member, the displacement of the outer peripheral member can be suppressed, so that the outer peripheral member is concentrically tightened with respect to the rotation shaft. Therefore, high concentricity of the processing member with respect to the rotation axis can be maintained. Further , according to the present invention, at least a part of the fixing member inserted through the flange portion and the outer peripheral member without any gap is on the flange portion, and the mounting portion is opposed to the axis of the rotating shaft and the mounting force. The fixing member is installed at a more effective position because it is configured to be within a range of 20 ° in the direction of application of the mounting force and 10 ° in the direction of reaction from the tangent line connected to the inner end of be able to. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary tool according to an embodiment of the present invention will be described below with reference to FIGS. here,
FIG. 1 is a side view of a woodworking cylinder of the present embodiment, and FIG. 2 is a front view of FIG. Each of FIGS. 1 and 2 partially shows a cross section. As shown in FIG. 1, a planer for woodworking as a rotary tool comprises a cylindrical planer body 10 having a cylindrical shape fixed via a bush 20 around the axis of a rotary shaft 1 (indicated by a two-dot chain line). Have. The plane body 10 is configured to rotate in the direction of the arrow 50 in FIG. In four places on the outer periphery of the plane body 10, there are knife grooves 11a-1.
1d are provided in each of the blade grooves.
2a to 12d are provided. In addition, each blade assembly 12
a to 12d are blades 13 (for processing a workpiece) using a preset countersunk screw 17, a preset nut 18, and the like.
And the back seat 14 are formed integrally, and the positional relationship between the cutting edge of the blade 13 and the back seat 14 is fixed and combined in advance. Further, for example, the blade assembly 12a is fastened and fixed to the side wall 10a of the plane body 10 by the fastening force of the fastening bolt 15 (in the direction of the arrow 30 in the figure). The direction of the arrow 30 corresponds to the operation direction of the present invention. As shown in FIGS. 1 and 2, the bush 20 has a flange portion 20a overlapping the end face of the plane body 10, and in this embodiment, two bushes 20 are provided at both ends of the plane body 10 with the flange portions 20a. It is inserted in contact. And
The bush 20 is fixed to the plane body 10 by two fixing bolts 16 at the position of the flange portion 20a. Further, a tapered pin 19 having a tapered shape that fixes the bush 20 so as to be relatively immovable with respect to the plane body 10 is provided in the insertion holes 10c and 20c provided at four places of the plane body 10 and the bush 20, respectively. It is inserted without any gap (so-called interference fit). The insertion holes 10c and 20c are
Since the plane body 10 and the flange 20a of the bush 20 are formed in a superposed state, the concentricity is high. The taper pin 19 is used for the bush 2 based on an analysis result described later.
0 is installed at a specific position (shown in FIG. 2) of the flange portion 20a, and by installing the taper pin 19 at this position, the plane body 10 and the bush 20 are concentric with the rotary shaft 1. It is tightened and the displacement of the cutting edge is also suppressed. The bush 20 corresponds to the inner peripheral member of the present invention, and includes the plane cylinder body 10, the blade assembly 12a to 12d.
Thus, the outer peripheral member of the present invention is configured. Also,
The tapered pin 19 corresponds to the fixing member of the present invention.
The fastening bolt 15 corresponds to the mounting means of the present invention, and the tightening force corresponds to the mounting force of the present invention. The blade 13 corresponds to the processing means of the present invention, and the blade grooves 11a to 11d correspond to the mounting portion of the present invention. As shown in FIG. 2, there is an O between the outer peripheral surface 20d of the bush 20 and the inner peripheral surface 10b of the plane body 10.
A space 21 closed by an (O) ring 22 is formed in the circumferential direction, and this space 21 communicates with the grease nipple 23 via a check valve (not shown). Therefore, by injecting a pressure medium (for example, grease) from the grease nipple 23, the inside of the space 21 can be maintained in a pressurized state. The pressure inside the space 21 can be released by the nipple 24. When the inside of the space 21 is pressurized by the pressure medium, the bush 20
(Between the O (O) rings 22) is pressed in the direction of the arrow 34 in the figure to reduce the inner diameter. Therefore, the inner diameter 20b of the bush 20 can correspond to the outer diameter 1b of the rotating shaft 1,
The concentricity of the plane body 10 with respect to the rotating shaft 1 can be enhanced (centering function). By the way, when each blade assembly is tightened by the tightening bolt 15, the blade 1
The mechanism by which the concentricity of No. 3 is reduced was clarified in the course of the present invention. Therefore, as described above, the tapered pin 19 for concentrically fixing the plane cylinder body 10 and the bush 20 to the rotary shaft 1 can be used, for example, to connect the blade assembly 12a to the tightening bolt 1.
5 is preferably installed at a specific position so that the displacement of the blade 13 can be minimized. A suitable installation position of the tapered pin 19 can be determined using, for example, a known finite element analysis.
Study 1 and Study 2 conducted using this finite element method analysis
Will be described with reference to FIGS. Here, FIG.
It is explanatory drawing explaining the influence which the fastening by a fastening bolt gives to the displacement of each part of a plane cylinder main body. FIG. 4 is a partially enlarged view of FIG. 1 and illustrates the effect of the installation position of the tapered pin on the displacement of each part of the plane cylinder body and the bush. FIG. 5 is a graph for explaining the influence of the position of the point at which the flange of the bush is fixed to the side surface of the plane body on the radial displacement of the blade. Here, a description of a specific analysis method and the like of the finite element method analysis will be omitted. [Study 1] First, in Study 1, when a predetermined tightening force is applied to the tightening bolt 15 to tighten each blade assembly, the stress received by each part of the plane cylinder main body 10 and the plane displaced by the stress. The displacement amount of each part of the trunk main body 10 can be examined using the finite element method analysis. As a result, for example, as shown in FIG.
The side wall 10a of the plane body 10 is
The vicinity is displaced in the direction of the arrow 40 in the drawing, and it can be confirmed that this displacement is the largest in the vicinity of the side wall 10a among the respective parts of the plane cylinder main body 10. Also, due to the influence of the displacement near the side wall 10a, the blade groove 11 on the inner peripheral surface 10b of the plane cylinder main body 10 is formed.
It can be confirmed that the vicinity of a is displaced in the direction of the arrow 42 in the figure, the diameter of the inner peripheral surface 10b increases, and concentricity decreases. Therefore, the blade assembly 1 is fixed by the tightening bolts 15.
When 2a is tightened, the cutting edge position of the cutting edge 13 is displaced in the direction of arrow 32 in the drawing, and if the amount of displacement of the cutting edge position of each cutting edge differs, the concentricity of the cutting edge position of the cutting edge 13 with respect to the rotating shaft 1 decreases. Will do. Also, every time the diameter of the inner peripheral surface 10b increases, that is, when the attachment and detachment of the blade assembly 12a is repeated, the relative position between the plane body 10 and the bush 20 fixed by the fixing bolts 16 having minute play. The position shifts, and the concentricity decreases due to accumulation of the shift. The displacement of each of these members can be confirmed by actual measurement. [Study 2] Next, in Study 2, the plane cylinder body 10 in which the bush 20 is fixed by the taper pin 19 is described.
In the above, when a predetermined tightening force is applied to all the tightening bolts 15 at four locations on the outer periphery to tighten each blade assembly, the stresses received by the respective parts of the plane cylinder body 10 and the respective parts of the plane cylinder body 10 that are displaced by the stresses. The displacement can be examined using finite element analysis. Plane cylinder body 10 and bush 2
0 is fixed by a taper pin 19, the concentricity is maintained, but the rigidity of the plane cylinder body 10 still varies, the tightening force of the tightening bolt 15 fluctuates, and the like. Positions vary. Therefore, it was studied below that the displacement of the cutting edge is reduced by providing the tapered pin 19 at an appropriate position to reduce the influence of the above-described variation. In this study, as shown in FIG. 4, a reference point P having a relatively small displacement even when the tightening bolt 15 is tightened, and a reference line n0 (see FIG. 4) connecting the reference point P and the axis 1a of the rotary shaft 1. 0 °) can be set. The reference point P is the inner end of the side wall 10a (the side receiving the tightening force of the tightening bolt 15) on the side of the rotating shaft 1 (the inner end of the mounting portion in the present invention), for example, the shaft center 1a and the blade groove 11a. Are provided on the tangent to Then, when the installation position of the taper pin 19 with respect to the reference point P and the reference line n0 is changed, the radial displacement W of the cutting edge position of the blade 13 is changed.
c (μm) can be considered. In addition, the installation position of the taper pin 19 is PCD (pitch) in the radial direction.
circle diameter) and change the reference line n0 in the circumferential direction.
Can be specified by changing the angle Θ (deg) with respect to. As a result, as shown in FIG. 5, for example, according to the finite element method analysis, the displacement amount Wc becomes small (in this embodiment, within 18 μm). The installation position is irrelevant to the radial direction, and the circumferential direction is 20 ° in the working direction (the direction of the arrow 30 in FIG. 4) of the tightening force of the tightening bolt 15 with respect to the reference line n0,
This is a position within a range of 10 ° in the reaction direction. Therefore, a suitable installation position (specific position) of the taper pin 19 is, for example, at least a part thereof is a boundary line n1 (−1) in FIG.
0 °) to the boundary n2 (+ 20 °). The displacement of each member when the tapered pin 19 is provided at a suitable position can be confirmed by actual measurement. According to the tensioning structure of the present embodiment configured as described above, the taper pin 19 for fixing the relative position of the plane body 10 to the bush 20 is moved to a specific position based on the result of the finite element analysis. Since at least a part of the taper pin 19 is provided at a position within the range of the boundary line n1 to the boundary line n2, the plane body 10 can be tightened concentrically with respect to the rotary shaft 1, The displacement of the plane body 10 with respect to the rotating shaft 1 can be suppressed, the radial displacement of the cutting edge of the blade 13 is small, the rigidity of the plane body 10 is not uniform, the variation in the tightening force of the tightening bolts 15, and the like. The variation in the position of the cutting edge in the radial direction can be reduced. Accordingly, it is possible to suppress the accuracy of the peripheral runout due to the displacement of the cutting edge position of the blade 13 within a predetermined value (for example, 20 μm). Further, by inserting (taper fitting) the taper pin 19 into each of the through holes 20c, 10c of the flange 20a and the plane body 10 in a state where the flange 20a of the bush 20 and the end face of the plane body 10 overlap each other. The bush 20 and the plane body 10 can be firmly fixed.
Further, in the present embodiment, the plane cylinder body 10 and the bush 2
The external force acting on zero is the tightening force when the blade assembly 12 is tightened by the tightening bolt 15, but is the case when another external force (for example, a pressing force received from the workpiece during processing) acts. However, the plane body 10 can concentrically tighten the plane body 10 with respect to the rotating shaft 1 without shifting with respect to the bush 20, and the outer peripheral runout accuracy of the cutting edge position of each blade 13 can be adjusted to a predetermined value. Accuracy can be maintained. [Other Embodiments] The present invention is not limited to the above-described embodiment, and various applications and modifications are conceivable. (A) In the above-described embodiment, the tapered pin 19 and the fixing bolt 16 are provided on the flange portion 20a side, but the installation positions of the tapered pin 19 and the fixing bolt 16 are not limited, and can be variously changed as necessary. It is. For example, the taper pin 19 and the fixing bolt 16 can be provided from the outer peripheral surface of the plane body 10 toward the bush 20. (B) In the above-described embodiment,
The bush 20 was fixed to the plane body 10 by inserting (tightly fitting) a tapered pin 19 into the insertion holes 10c and 20c without any gap.
Various fixing methods can be used as needed as long as the fixing method does not relatively displace the plane body 10 with the plane cylinder body 10. For example, a rod-shaped pin slightly larger in diameter than the insertion holes formed in both members is cooled in advance, and the members are firmly fixed at room temperature by inserting the pins into the insertion holes. It may be a fixing method of fixing by fitting the projection and the projection. Further, although the tapered pins 19 are provided at four positions, the number of the tapered pins 19 is not limited, and can be variously changed as needed. (C) In the above-described embodiment,
Although the description has been given of the configuration in which the blade assemblies 12a to 12d are fixed to the blade grooves 11a to 11d of the plane body 10 by the fastening bolts 15, the fixing method for fixing the blade to the main body is not limited. For example, the present invention can be applied to a plane cylinder that fixes a blade using centrifugal force as described in Japanese Utility Model Publication No. 2-28014. (D) In the above-described embodiment,
Although the tightening structure of the woodworking cylinder has been described as a rotating tool, the present invention is applied to tools that perform various kinds of processing (eg, polishing, cutting, etc.) by rotating processing means other than the woodworking cylinder. Structure can be applied. (E) In the above-described embodiment,
Although the installation position of the taper pin 19 is set based on the result of the finite element analysis, it can be set using various types of stress analysis other than the finite element analysis. (F) In the above-described embodiment,
Although the bush 20 is provided at two places at both ends of the plane body 10, the present invention can be applied to a rotary tool having a short axial length and having a bush at one place on one side. As described above, according to the present invention,
Even when an external force acts on a member installed around the rotation shaft, the member can be tightened concentrically with respect to the rotation shaft, and high concentricity of the member with respect to the rotation shaft can be maintained. It is possible to realize a rotating tool tightening structure that can be performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a woodworking planner according to an embodiment of the present invention. FIG. 2 is a front view of FIG. FIG. 3 is an explanatory diagram for explaining the effect of tightening by a tightening bolt on displacement of each part of a plane cylinder main body. FIG. 4 is a partially enlarged view of FIG. 1 and illustrates the effect of the installation position of the tapered pin on the displacement of each part of the plane cylinder main body and the bush. FIG. 5 is a graph illustrating an influence of a position of a point at which a flange portion of a bush is fixed to a side surface of a plane body on a radial displacement of a blade. FIG. 6 is a side view of a conventional woodworking cylinder. FIG. 7 is a front view of FIG. 6; DESCRIPTION OF SYMBOLS 1 ... Rotating shaft 10 ... Plane cylinder main body 11a-11d ... Cutting groove 12a-12d ... Cutting blade assembly 13 ... Cutting blade 15 ... Tightening bolt 16 ... Fixing bolt 19 ... Taper pin 20 ... Bushing, flange ... 20a

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-94131 (JP, A) JP-A-62-75902 (JP, U) JP-B3-17-117 (JP, B2) (58) Field (Int. Cl. ⁷ , DB name) B27G 13/00 B23C 5/26 B27C 1/02

Claims (1)

(1) In a rotary tool, an outer peripheral member is disposed around an axis of a rotating shaft via an inner peripheral member, and the inner and outer peripheral members rotate concentrically with the rotating shaft. The inner peripheral member has a flange portion overlapping the end surface of the outer peripheral member
In order to fix the relative position of the outer peripheral member with respect to the inner peripheral member, between the flange portion and the outer peripheral member ,
Is the pin inserted without gap between the flange and the outer peripheral member?
A fixing member comprising: a processing means for processing a workpiece;
Mounting means for mounting the working means to the mounting portion of the outer peripheral member.
Provided, when an attachment force is applied by the attachment means , in order to suppress a radial displacement of the outer peripheral member with respect to the rotation shaft within a predetermined value , at least a part of the fixing member includes:
On the flange, the axis of the rotating shaft and the mounting force
From the tangent connecting the inner end of the mounting portion facing the
20 ° in the direction of application of the mounting force about the axis,
A tightening structure for a rotary tool, wherein the working tool is within a range of 10 degrees .