JPH02283952A - Mechanism for converting rotary motion to linear motion - Google Patents

Abstract

PURPOSE:To apply a little larger force to a ring member or a feed shaft so as to force them to slip and to freely move them in the axial direction by rotating a roller centering round the axis inclined to a feed shaft as the feed shaft is rotated to produce component force for moving a ring member along the feed shaft. CONSTITUTION:When the drawing force of an inner case 3 is removed, the case 3 is drawn in an outer case 2 by the force of a spring 7. At this time, the case 3 is a little rotated to the case 2 and drawn therein, and a roller 4 is tilted at a designated angle to a feed shaft, so that the outer peripheral surface of the central portion of the roller 4 is pressed to the outer peripheral surface of the shaft. In such a condition, a ring member formed by the cases 2, 3 is kept from rotating on its axis, and the shaft 1 can be moved freely in the axial direction, so that when the shaft 1 is rotated, the roller 4 inclined to the shaft 1 is turned round along with the shaft 1. With this motion, the component force for sliding the cases 2 and 3 along the shaft 1 is produced, so that the cases 2, 3 and the ring member including each roller 4 are moved rectilinearly along the shaft 1.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a mechanism for converting rotational motion into linear motion as one of mechanical elements, and particularly relates to a mechanism for converting rotational motion into linear motion as one of mechanical elements, and in particular, relates to a mechanism for converting rotational motion into linear motion as one of mechanical elements, and particularly to a mechanism for converting rotational motion into linear motion as one of mechanical elements. Relating to something that is equipped with.

(Prior art) This type of machine (R), which displaces a feed shaft and an annular member attached around the shaft, is well known for its feed screw mechanism, and is incorporated into various mechanical equipment. It is applied to

(Problem to be solved by the invention) The feed screw mechanism uses a long male threaded feed screw and a pole nut or a normal female threaded nut member, and has high feeding accuracy and can take a sufficiently large linear motion force. It also has excellent features such as high static torque. If you want to improve the shortcomings of the feed screw mechanism, remove the screw connection between the screw foot and the nut and tighten the nut part.
4 cannot be moved at ultra-high speed, and machining a long screw shaft is troublesome and expensive.

An object of the present invention is to provide a mechanism for converting rotational motion into linear motion with a novel and unprecedented configuration, and in particular,
A simple round bar or cylindrical body without a male thread can be used as the feed shaft, and rotational motion can be converted into linear motion, and the annular member around the feed shaft can be quickly slipped without relying on this conversion motion. The purpose is to provide a mechanism that can be moved.

(Means for Solving the Problems) The mechanism for converting rotational motion into linear motion according to the present invention has the following features:
It has a long feed shaft with a cylindrical outer periphery and an annular member attached around this feed shaft, and three rollers are attached to the inner periphery of this annular member at positions that divide the inner periphery into three equal parts. Each roller is rotatable at a predetermined angle with respect to the feed shaft and is in contact with the feed shaft.

(Function) When the annular member is allowed to move linearly along the feed shaft and is prevented from rotating around the heel, and the feed shaft is rotated, the roller rotates as the feed shaft rotates. rotates around an axis that is inclined with respect to the feed axis, so a component force is generated that moves the annular member along the feed axis.

(Embodiment) FIGS. 1, 2, and 3 show the configuration of an embodiment of the present invention. In each figure, 1 is a feed shaft having a long outer periphery and a cylindrical surface, and 2 and 3 are an outer case and an inner case of annular members mounted around this feed shaft 1. Outer case 2
The inner case 3 is configured to have a cylindrical shape, and the inner case 3 is configured to fit into the inner periphery of the outer case 2, so that the outer case 2 and the inner case 3 can be slid relative to each other in the axial direction. There is.

Three rollers 4 are attached to the inner peripheral portion of an annular member consisting of an outer case 2 and an inner case 3 at equal intervals. One end of the roller 4 is supported by a self-aligning sliding bearing 5 attached to one end surface of the outer case 2, and the other end of the roller 4 is supported by a self-aligning sliding bearing 6 attached to one end surface of the inner case 3. is supported by As mentioned above, the outer case 2 and the inner case 3 are able to slide in the axial direction relative to each other, but a spring 7 is loaded between the two cases, and the force of this spring 7 causes both the cases 2 and 2 to slide in the axial direction. and 3 are constantly biased in the direction of approaching each other (the direction of drawing case 3 into case 2). The state shown in FIG. 1 shows the state in which the inner case 3 is pulled out against the force of the spring 7. At this time, the roller 4, whose both ends are supported by self-aligning sliding bearings 5 and 6, is parallel to the feeder 1. It's happening. When the force applied to the inner case 3 is removed from this state, the inner case 3 is pulled into the outer case 2 by the force of the spring 7, but at this time, the inner case 3 rotates slightly relative to the outer case 2 and is pulled in. As shown in FIG. 2, the roller 4 is tilted at a predetermined angle with respect to the feeder 1, and in this inclined state, the outer peripheral surface of the central portion of the roller 4 is aligned with the outer periphery of the feeder 1 as shown in FIG. (a, b, c indicate the contact points between each roller 4 and the feed shaft 1).

In the state shown in FIGS. 2 and 3, the annular member consisting of the outer case 2 and the inner case 3 is prevented from rotating around its axis, and is allowed to move freely in the axial direction of the feeder 1. When the roller 1 is rotated, the roller 4, which is tilted with respect to the feed shaft 1, rotates along with the feed shaft 1.
Along with this, a component force is generated that causes the outer case 2 and the inner case 3 to slide along the feed shaft 1, and the annular member that integrally includes the cases 2 and 3 and each roller 4 moves in a straight line along the feed shaft 1. Exercise.

Furthermore, when the feed shaft 1 is made axially movable but not rotatable, and the annular member is rotated, an axial force acts on the feed shaft 1 from the roller 4, and the feed shaft 1 will move linearly in the axial direction.

The above movement is similar to that of the feed screw mechanism, but in the mechanism of the present invention, the mechanical coupling force between the feed shaft 1 and the annular member is very weak, and a certain amount of force is applied to the annular member to move it in the axial direction. If you want to move it, you can easily slip it and move it.

(Effects of the Invention) As explained in detail above, in the mechanism of the present invention, the mechanism is similar to the feed screw mechanism between the feed shaft having a long cylindrical outer periphery and the annular member attached around the shaft. Rotary motion can be converted into linear motion.

However, there is no external thread on the outer periphery of the feed shaft, and the mechanism of the present invention can be manufactured at a very low cost because it can be a simple round bar or cylinder. In addition, the mechanical coupling force between the feed shaft and the annular member is very weak, and by applying a slightly larger force to the annular member or the feed shaft, the two can be made to slip, regardless of the conversion between rotational and linear motion. can be moved axially.

[Brief explanation of drawings]

FIG. 1 is a partially sectional front view of a mechanism for converting rotational motion into linear motion according to an embodiment of the present invention (in this figure, the roller 4 is in a state parallel to the feed shaft 1), and FIG. 2 is the same as above. FIG. 3 is a plan view of main parts showing the normal state in which the roller 4 is tilted with respect to the feed shaft 1 in the mechanism, and FIG. 3 is a side view showing the relationship between the feed shaft 1 and each roller 4 in the normal state of the same mechanism. . 6...Self-aligning sliding bearing 7...Spring

Claims (1)

[Claims] It has a long feed shaft with a cylindrical outer periphery and an annular member attached around this feed shaft, and three rollers are attached to the inner periphery of this annular member at positions that divide the inner periphery into three equal parts. A mechanism for converting rotational motion into linear motion, wherein each roller is rotatable at a predetermined angle with respect to the feed shaft and is in contact with the feed shaft.