JPH0767641B2 - Holder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to solve the following problems.

(Field of Industrial Application) This invention relates to a machine tool,
The present invention relates to a tool such as a drill or a holder that holds a workpiece to be processed.

(Prior Art) A conventional holder having a number of grooves formed on the inner peripheral surface of a fastening cylinder for inserting a held object is a fastening tube when fastening the held object. Even if there is an oil film between the inner peripheral surface of and the outer peripheral surface of the object to be held, the oil can be allowed to escape to the groove, and the object to be held can be firmly held. However, with the structure as described above, it is difficult and difficult to cut the groove on the inner surface of the fastening cylinder, and there is a problem that the product price becomes high. Further, when the inner diameter of the fastening cylinder becomes small, there is a problem that it becomes extremely difficult to cut a groove in the fastening cylinder so that it cannot be carried out.

(Problems to be Solved by the Invention) Except for the above-mentioned conventional problems, the present invention, when holding and holding an object to be held, releases it even if an oil film is present between the object and the object to be held firmly. In addition, even if such a thing is provided, it is easy to process and can be provided at a low cost, and further, a holding tool that can be implemented even if the inner diameter of the fastening tube is small is provided. Is what you are trying to do.

The configuration of the present invention is as follows.

(Means for Solving Problems) The invention of the present application employs means as described in the claims, and its operation is as follows.

(Operation) When the base of the object to be held is inserted into the insertion hole of the fastening tube and the turning tube is turned, the turning tube moves to the side of the larger diameter portion of the fastening tube. As a result, the fastening cylinder is compressed inwardly via the roller between the rotating cylinder and the fastening cylinder, and the inner peripheral surface of the fastening cylinder presses against the outer peripheral surface of the held object to hold it. Hold. When the above-mentioned fastening cylinder is compressed, between the portions pressed by the roller group, there is a slight gap between which the oil can escape between the inner circumferential surface of the fastening cylinder and the outer circumferential surface of the held object. . Therefore, when there is an oil film between the inner peripheral surface of the fastening cylinder and the outer peripheral surface of the held object, the oil inside the portion pressed by the roller group can escape during the above.

(Example) Hereinafter, drawings showing an example of the present application will be described. In FIGS. 1 to 3, reference numeral 1 is a main body, and 2 is a connecting portion provided at a base portion thereof, which is a portion adapted to be attached to a spindle of a machine tool. Reference numeral 2a indicates a holding portion provided at the tip of the main body 1. In the holding portion 2a, 3 is a fastening cylinder integrally formed with the main body 1, which is configured to be elastically deformable in the radial direction, and has an insertion hole 4 into which an object to be held is inserted. Reference numeral 5 denotes a fastening surface on the inner peripheral surface of the fastening tube 3. Reference numeral 7 denotes an outer peripheral surface of the fastening cylinder 3, which is formed in a tapered shape in which the side of the connecting portion 2 becomes thick. Next, 17 is a rotary cylinder disposed around the mounting cylinder 3, and an inner peripheral surface 18 thereof is formed in a tapered shape parallel to the outer peripheral surface 7. Further, a well-known spanner hook groove 18 is formed on the outer peripheral surface. Next, 21 is a guide tube disposed between the fastening tube 3 and the rotating tube 17, which is a bird cage shape with a plurality of guide holes 22 formed as is well known, and each guide hole 22 has a roller. Each 24 is rotatably retained. As is well known, the rollers 24 are arranged in a twisted position having a certain angle with respect to the central axis of the guide cylinder 21 (corresponding to the central axis of the fastening cylinder 3). The rollers 24 are divided into a plurality of roller groups 24a in the circumferential direction of the fastening cylinder 3. The distance between the roller groups 24a is determined by the distance between the portions 3a, 3a of the fastening cylinder 3 that are pressed by the roller groups 24a toward the object to be held when the fastening cylinder 3 is reduced in diameter. In the portion 3b, the gap is defined so that a clearance 32 for oil escape can be formed between the inner peripheral surface 5 of the fastening cylinder 3 and the outer peripheral surface of the held object. In this example, one roller group 24 is attached to the central axis of the fastening cylinder 3.
The angle formed by the portions between the roller groups on the central axis is about 1/2 of the angle formed by a. 25
Is a rubber seal for dustproof, 26 is a ring for holding the seal, 27
Shows the circlips for retaining.

Next, an operation of holding the held object 31, for example, the cutting tool (may be a work piece) by using the holding tool having the above configuration will be described. First, the base of the cutting tool is inserted into the insertion hole 4. Next, the rotating cylinder 17 is rotated clockwise in FIG.
Then, the large number of rollers 24 are guided by the guide tube and rotate in the state of the twisted positions as described above. Therefore, by rotating the rotating cylinder 17, a large number of rollers 24 roll on the outer peripheral surface 7 while rotating between the outer peripheral surface 7 of the fastening cylinder 3 and the inner peripheral surface 18 of the rotating cylinder 17, respectively. Along the spiral tube 3, the spiral tube 3 advances toward the large-diameter portion 8 side. As a result, the rotating cylinder 17 also advances in the same direction. When the rotating cylinder 17 advances toward the large-diameter portion 8 in this way, the fastening cylinder 3 is compressed by the rotating cylinder 17 via the roller 24, and the diameter of the fastening cylinder 3 is reduced. As a result, the fastening surface 5 comes into pressure contact with the outer peripheral surface of the cutting tool and strongly tightens it.

When the rotating cylinder 17 is rotated to contract the fastening cylinder 3 as described above, the rollers 24 are arranged separately in the roller group 24a. Therefore, the portion indicated by reference numeral 3a in FIG. 2 is the roller group.
The object to be held 31 is strongly pressed by 24a. Therefore, while the portion 3a strongly presses the held object 31, a slight gap 32 is formed between the inner peripheral surface of the portion 3b and the outer peripheral surface of the held object 31. Therefore, even if an oil film exists between the inner peripheral surface 5 of the fastening cylinder 3 and the outer peripheral surface of the held object 31, the inner peripheral surface of the portion 3a and the outer peripheral surface of the held object 31 are The oil present in between can escape towards the gap 32. As a result, in the above-mentioned portion 3a, the inner peripheral surface thereof and the held object 31
It is possible to remove oil from the outer peripheral surface of the object, so that the outer peripheral surface of the object to be held 31 can be pressed securely, and the object to be held 31 can be reliably held with a large frictional force.

In the state where the object to be held 31 is fastened and held as described above, the fastening cylinder 3 and the object to be held 31 are rotated by rotating the main body 1, and the object to be held is machined as well known (example Cutting).

Next, FIGS. 4 to 6 show examples in which the plurality of rollers 24e in each roller group 24ae are arranged differently. The arrangement of the large number of rollers 24e in the roller group 24ae can take various arrangements other than the arrangements shown in these figures.

In addition, parts that are considered to be the same or equivalent in configuration to those in the previous figure in terms of function are denoted by the same reference numerals as those in the previous figure with the letter e added to omit redundant description.

(Also, in the following figures and the like, alphabetical letters f and g are sequentially given in order to omit the overlapping description.) Next, FIG. 7 shows the circumferential size of each roller group 24af and the rollers. This shows an example in which the ratio of the size between the groups in the circumferential direction is different. In this example, the size of the latter is about 1/5 of the size of the former.

Next, FIG. 8 shows an example in which the number of roller groups is different, and shows an example in which six roller groups 24ag are arranged around the fastening cylinder 3g. Also in this embodiment, the angle between the roller group and the center axis of the fastening cylinder is about 1/5 of the angle between the roller groups and the center axis.

The ratio of the size of the roller group in the circumferential direction to the size of the portion between the roller groups in the circumferential direction, or the number of the roller groups arranged around the fastening cylinder is determined by the inner surface of the fastening cylinder and the object to be held. It is preferable to set the clearance according to the diameter and thickness of the fastening cylinder so that the above-mentioned clearance is formed between the fastening cylinder and the outer peripheral surface.

(Effects of the Invention) As described above, according to the present invention, when it is desired to hold an object to be held, the base of the object to be held is inserted into the insertion hole 4 of the fastening tube 3 and the rotating tube 17 is rotated. By moving it to the larger diameter side of the fastening tube 3, the turning tube 17 presses the fastening tube 3 through the roller 24, and the inner peripheral surface 5 fastens the base of the held object. And there is a feature that can hold it.

Moreover, when the tightening cylinder 3 is compressed by rotating the rotating cylinder 17 as described above, the rollers 24 are arranged so as to be divided into a plurality of groups 24a, 24a. Even if there is an oil film between the inner peripheral surface 5 of the mounting cylinder 3 and the outer peripheral surface of the held object 31, as described above, the oil inside the portion 3a pressed by the roller group 24a in the fastening cylinder 3 is Can escape into the gap 32 formed inside the part 3b between them,
At the pressed portion 3a, there is an effect that the oil film can be cut and the object to be held can be reliably held with a large frictional force.

In addition, even the one that allows the oil to escape as described above,
Since the roller group 24a having the above arrangement makes this possible, the inner peripheral surface 5 of the fastening cylinder 3 has the feature that it may be a simple round hole. This means that, firstly, in the case of manufacturing, the processing of the inner peripheral surface 5 is significantly simpler than that of the conventional one having a groove, and as a result, there is a great effect that it can be provided at a low cost. Secondly, there is an effect that it can be carried out even when it is difficult to form the groove as in the conventional case because the inner diameter of the fastening cylinder 3 is small.

[Brief description of drawings]

The drawings show an embodiment of the present application, and FIG. 1 is a half sectional view,
FIG. 2 is a sectional view taken along the line II-II, FIG. 3 is a side view in which only the rotary cylinder is partially broken, and FIGS. 4 to 6 are developments showing different examples of the arrangement of rollers in the roller group. FIG. 7, FIG. 8 and FIG. 8 are cross-sectional views showing different examples of the arrangement of the roller groups (cross-sectional view at the same position as in FIG. 2). 3 ... Tightening cylinder, 4 ... Insert hole, 17 ... Rotating cylinder, 24 ... Roller, 24a ... Roller group.

Claims (1)

[Claims] 1. A hollow cylindrical shape that is elastically deformable in the radial direction,
Moreover, the inside has an insertion hole for an object to be held whose one end is open, while the outer peripheral surface has a tapered cylinder, and a rotary cylinder is relatively rotatable around the above-mentioned cylinder. It is movably arranged and moves in the axial direction of the fastening cylinder by turning the rotation barrel with respect to the fastening cylinder between the outer peripheral surface of the fastening cylinder and the inner peripheral surface of the rotation barrel. In order to be able to do so, by interposing a large number of rollers each having a twisted position with respect to the axis of the fastening cylinder, the rotating barrel is rotated to move it to the larger diameter side of the fastening cylinder. In the holder in which the diameter of the tightening cylinder is reduced by means of which the object to be held is tightened by its inner peripheral surface, the plurality of rollers are divided into a plurality of roller groups in the circumferential direction of the tightening cylinder. In addition, when the diameter of the tightening cylinder is reduced as described above, the distance between the respective roller groups is different depending on each roller group in the tightening cylinder. Between the portions that are pressed toward the object to be held by the inner peripheral surface of the fastening cylinder and the outer peripheral surface of the object to be held so that a clearance for oil escape can be formed. And retainer.