JP4643421B2 - Nut locking mechanism - Google Patents

Description

  The present invention relates to a loosening prevention mechanism for a nut screwed to a bolt.

  As a mechanism to prevent loosening of nuts screwed to bolts, a mechanism that uses a double nut or a mechanism that attaches a lock nut that has a set screw that crushes the screw thread of the bolt is generally adopted. Has the problem of requiring an extra space for two nuts in the bolt, and the mechanism for attaching the lock nut cannot be reused.

  In order to solve this problem, a bolt that does not require extra space and can be reused as a nut loosening prevention mechanism is provided with a plurality of longitudinal grooves extending in the axial direction on the outer periphery of the threaded portion of the bolt. A mechanism has been proposed in which a ball plunger is screwed into a lock screw hole provided in the shaft and the nut is loosened by engaging the ball plunger with a vertical groove of a bolt (see, for example, Patent Document 1). In the embodiment described in Patent Document 1, six longitudinal grooves of bolts that can be engaged with the ball plunger are provided in the circumferential direction.

JP 2003-184847 A

  The nut locking mechanism described in Patent Document 1 does not require an extra space in the bolt and can be reused, but the nut tightening position where the ball plunger can be engaged with the vertical groove of the bolt is limited, and the nut Cannot be locked at the optimum screw tightening position. For example, if six longitudinal grooves are equally arranged in the circumferential direction of the bolt, the screw tightening position of the nut is limited to a rotation position at intervals of 60 °. In order to lock the nut at the optimal screw tightening position, the number of longitudinal grooves can be increased. However, if the number of longitudinal grooves is increased, the threaded portion of the bolt is largely divided to secure the tightening force. Such a screw tightening function is hindered.

  Accordingly, an object of the present invention is to provide a nut locking mechanism capable of locking a nut at an optimum screw tightening position without hindering the screw tightening function.

In order to solve the above-described problems, the present invention provides a nut locking mechanism for locking a nut screwed to a bolt, and a plurality of tilted vertical members extending on the outer peripheral surface of the nut while being inclined with respect to the axial direction. A locking member is provided with a groove, and a fixing plate having a long hole extending in the axial direction of the nut is disposed outside the nut, and the nut is fitted into the inclined vertical groove of the nut to lock the nut. Are attached to be movable in the axial direction of the long hole, and the plurality of inclined vertical grooves have an overlapping margin in which adjacent inclined vertical grooves overlap each other in the circumferential direction of the outer peripheral surface of the nut. is tilted with respect to the axial direction, so as to fit the movable locking member in the axial direction to one of the inclined longitudinal grooves of the slot, the circumferential force to be loosen the nut F, the circumferential Of the direction force F When the component force in the direction along the oblique longitudinal groove is Fy, the component force in the direction perpendicular thereto is Fx, and the friction coefficient between the lock member and the sidewall of the inclined longitudinal groove is μ, the side wall by the component force Fx The configuration in which the inclined longitudinal grooves are inclined with respect to the axial direction so that the frictional resistance μFx is equal to or greater than the component force Fy is employed.

That is, the outer peripheral surface of the nut is provided with a plurality of inclined longitudinal grooves extending obliquely with respect to the axial direction, outwardly of the nut, by disposing the fixing plate having a long hole extending in the axial direction of the nut, this A lock member that locks the nut by being fitted into the inclined vertical groove of the nut is attached to the fixed plate so as to be movable in the axial direction of the long hole, so that the lock member can be fitted into the inclined vertical groove at any rotational position of the nut. Thus, the nut can be locked at the optimum screw tightening position without hindering the screw tightening function.

  By using the plunger biased so as to be fitted into the inclined vertical groove, the locking member can be easily fitted into the inclined vertical groove only by moving the plunger as the locking member in the axial direction.

The nut loosening prevention mechanism of the present invention is provided with a plurality of inclined longitudinal grooves extending obliquely with respect to the axial direction on the outer peripheral surface of the nut, and a fixing having a long hole extending in the axial direction of the nut on the outer side of the nut. A lock member that locks the nut by being fitted in the slanted vertical groove of the nut is attached to this fixed plate so that it can move in the axial direction of the long hole, so that it can be locked at any rotational position of the nut. Since the member is fitted into the inclined longitudinal groove, the nut can be locked at the optimum screw tightening position without hindering the screw tightening function.

  By making the lock member a plunger biased so as to be fitted into the inclined vertical groove, the plunger as the lock member can be easily fitted into the inclined vertical groove only by moving in the axial direction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a clamp 1 employing a nut locking mechanism according to the present invention. The clamp tool 1 has a pair of arcuate and U-shaped cross-sections of clamp pieces 2a and 2b that are connected to each other by a connecting member 3 so that the base ends can be opened and closed. The attached bolt 5 is passed through the tip of the other clamp piece 2b, the nut 6 is screwed to the tip of the bolt 5, and the cylindrical part of the mechanical device or the like is clamped by the pair of clamp pieces 2a, 2b. is there.

As shown in FIGS. 2 and 3, the outer peripheral surface of the nut 6 is provided with a plurality of inclined vertical grooves 6 a extending inclined with respect to the axial direction, and a screw tightening knob 6 b on the base end side. Is provided. Further, at the tip of the clamp piece 2b, a base plate 7 having a notch recess 7a through which the bolt 5 is passed and a fixing plate 8 having a long hole 8a extending in the axial direction toward the front of the nut 6 are perpendicular to each other. A plunger 9 as a lock member that locks the nut 6 can be moved in the axial direction of the long hole 8a in the fixed plate 8 by being fitted into the inclined longitudinal groove 6a of the nut 6 to which the coupled fixing member is attached and screwed. Is attached to.

  As shown in FIG. 4, the plunger 9 urges a pin 9c fitted into the casing 9b at the tip of the knob 9a toward the tip side by a coil spring 9d so as to be fitted into the inclined vertical groove 6a of the nut 6. The pair of nuts 10 are attached so as to be movable in the axial direction of the long hole 8a. As shown in FIG. 4B, when the knob 9a is pulled and rotated 90 °, the pin 9c is locked in a state of being pulled out from the inclined vertical groove 6a, and the knob 9a is rotated 90 ° in the reverse direction and released. Then, as shown in FIG. 4A, the pin 9c urged by the coil spring 9d is fitted into the inclined vertical groove 6a.

  As shown in FIG. 5, when a force F for loosening the nut 6 is applied, the pin 9c of the plunger 9 fitted in the inclined vertical groove 6a has a component force in the direction of the inclined vertical groove 6a as its reaction force. Fy and a component force Fx in the direction perpendicular thereto act. The pin 9c tries to move in the direction of the inclined vertical groove 6a by the component force Fy, but the movement of the pin 9c is blocked by the frictional resistance μFx with the side wall by the component force Fx, and the loosening of the nut 6 by the force F is stopped.

  6 and 7 show a modification of the nut locking mechanism. In this modified example, the fixing plate 8 is coupled to the base plate 7 with the long hole 8a being shifted from the front of the nut 6, and the nut is connected to the long hole 8a through the slide plate 11 attached to be movable in the axial direction. A plunger 9 to be fitted into the 6 inclined vertical grooves 6a is attached. The slide plate 11 is attached to the long hole 8 a of the fixed plate 8 with a bolt 12 and a wing nut 13. Other parts are the same as those of the embodiment.

  FIG. 8 shows a mill pot 21 of a planetary ball mill using the clamp tool 1. This mill pot 21 is rotatably supported by a bearing 24 on upper and lower rotary tables 23 via a casing 22, and a sun gear (not shown) in which a planetary gear 25 attached to the outer periphery of the casing 22 is provided on a central shaft 26. , And revolves around the central axis 26, and the object to be crushed from the side of the upper lid 21a is crushed by a ball inserted therein. The crushed object is taken out by opening the lower lid 21c attached to the cylindrical discharge port 21b at the lower end, and the clamp 1 is used to attach the lower lid 21c to the discharge port 21b.

  The clamp tool 1 includes ferrules 27a and 27b provided at the lower ends of the discharge port 21b and the lower lid 21c between a pair of clamp pieces 2a and 2b having a U-shaped cross section, and tip portions of the clamp pieces 2a and 2b. Is tightened with the bolt 5 and the nut 6 so that the ferrules 27a and 27b are clamped and the lower lid 21c is attached to the discharge port 21b.

  In the embodiment described above, the lock member used in the nut locking mechanism is a plunger, but the lock member may be a screw-type pin or the like.

The front view which shows the clamp tool which employ | adopted the nut locking mechanism which concerns on this invention The front view which expands and shows the locking mechanism part of the nut of FIG. Side view of FIG. a is a cross-sectional view taken along the line IV-IV in FIG. 3, and b is a cross-sectional view showing a state where the pin of the plunger of a is pulled out from the inclined vertical groove of the nut. The front view explaining the engagement state of the pin of FIG. The front view which shows the modification of the nut locking mechanism of FIG. Sectional drawing along the VII-VII line of FIG. A longitudinal sectional view showing a mill pot of a planetary ball mill using the clamp device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Clamp tool 2a, 2b Clamp piece 3 Connecting member 4 Pin 5 Bolt 6 Nut 6a Inclined vertical groove 6b Knob part 7 Base plate 7a Notch recessed part 8 Fixed plate 8a Long hole 9 Plunger 9a Knob 9b Casing 9c Pin 9d Coil spring 10 Nut 11 Slide plate 12 Bolt 13 Wing nut 21 Mill pot 21a Upper lid 21b Discharge port 21c Lower lid 22 Casing 23 Rotary table 24 Bearing 25 Planetary gear 26 Center shaft 27a, 27b Ferrule

Claims (2)

In the nut locking mechanism for locking the nut (6) screwed to the bolt (5), a plurality of inclined longitudinal grooves (6a) extending obliquely with respect to the axial direction on the outer peripheral surface of the nut (6) A fixing plate (8) having a long hole (8a) extending in the axial direction of the nut (6) is disposed outside the nut (6), and the nut is attached to the fixing plate (8). A lock member fitted in the inclined vertical groove (6a) of (6) to lock the nut (6) is attached so as to be movable in the axial direction of the elongated hole (8a), and the plurality of inclined vertical grooves (6a) are attached. The adjacent inclined longitudinal grooves (6a, 6a) are inclined with respect to the axial direction so that the entire width of the grooves (6a) overlaps with each other in the circumferential direction of the outer peripheral surface of the nut (6). The locking member that can move in the axial direction of the hole (8a) F is the circumferential force to loosen the nut (6) so as to fit in the longitudinal groove (6a), and the component force in the direction along the inclined longitudinal groove (6a) of this circumferential force F. Fy, where Fx is a component force in a direction perpendicular to this and Fx is a friction coefficient between the lock member and the side wall of the inclined longitudinal groove (6a), the frictional resistance μFx against the side wall due to the component force Fx is A nut loosening prevention mechanism characterized in that the inclined longitudinal groove (6a) is inclined with respect to the axial direction so as to be equal to or greater than the force Fy.   The nut locking mechanism according to claim 1, wherein the lock member is a plunger (9) biased so as to be fitted into the inclined vertical groove (6a).

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