JPS60211158A - Rectilinear feed mechanism - Google Patents

Abstract

PURPOSE:To eliminate an impact and a vibration from start to finish in motion of a slider, by forming a rack in the slide, while installing a roller, and installing a pinion to be engaged with the rack and a plate cam both in a rotary shaft. CONSTITUTION:A rack 7 is formed on the side facing on a rotary shaft 1 of a slider, and each of rollers 10, 11 and 12 is set up in front and rear parts of the rack, while a pinion 14 to be engaged with the rack 7 and plate cams 8 and 9 feeding these rollers 10, 11 and 12 both are installed in this rotary shaft 1. With this constitution, with these plate cams 8 and 9, the slider 5 performs gentle acceleration or deceleration so that an impact and a vibration from start to finish in motion of the slider 5 are eliminable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a linear feed mechanism that converts rotational motion into linear motion.

(Background Art) In general, to convert rotational motion into long-stroke linear motion, for example, racks and screws, screws and nuts are used.

In such a transmission mechanism, the motion characteristics of the driving node (rotating body) directly become the motion characteristics of the driven node (sliding body), but for this reason, especially when the rotating body is driven by a motor etc., the movement characteristics of the sliding body are There was a problem in that shock and vibration were likely to occur at the end.

To prevent these shocks and vibrations, a device, such as a servo motor, is required to properly control the drive of the rotating body, that is, the speed at which the motor starts and stops, which increases the size, complexity, and cost of the device. It had the disadvantage of inviting close-ups.

Furthermore, in the above transmission mechanism, the stopping position of the sliding body completely depends on the stopping angle of the rotating body, so it is necessary to strictly control the stopping angle of the rotating body in order to accurately maintain the stopping position of the sliding body. However, even if this is done, it is not possible to eliminate, for example, backlash in gear meshing, and therefore a high degree of stopping accuracy cannot be expected.

(Purpose of the invention) This invention was made by focusing on these problems.
It eliminates shocks and vibrations at the beginning and end of the movement of the sliding body without having to particularly precisely control the drive of the rotating body, and
The purpose is to improve the positioning accuracy of sliding bodies.

(Structure and operation of the invention) Therefore, the present invention forms a rack along the sliding direction on the sliding body on the output side, and also arranges rollers at the front and rear of the sliding body, and a rack on the rotating shaft on the input side. A pinion is provided that meshes with the rotating shaft to move the sliding body linearly at a constant speed as the rotating shaft rotates at a constant speed, and the sliding body is started by feeding the sliding body through rollers before and after the equidistant area of the sliding body. A cam is installed to start the sliding body, and in the stopped area, move the sliding body in any direction through a roller. A stop part is provided to prevent the material from being sent out.

That is, as the cam rotates at a constant speed of the rotating shaft, when the roller disposed at the front of the sliding body rises from the stop to the shaped part,
The sliding body begins to be pushed through the rollers, and the speed increases with a gradual rise.

At the point when the sliding body moves to the equidistant range, when the rack and the pinion engage, the roller is removed from the cam almost at the same time, and from then on, the sliding body moves through the rack and the pinion to a predetermined stroke along with the uniform motion of the rotating shaft. Go straight at a constant speed.

When the rack comes off the binion almost at the same time as the roller disposed at the rear of the sliding body is placed on the cam shape, from this point on, the cam is again attached to the sliding body via the roller as the rotating shaft rotates at a constant speed. While feeding is applied and the roller is gradually decelerated, when the roller moves to the stop portion, the sliding body is stopped.

Therefore, the sliding body begins to move as the rotating shaft rotates at a constant speed,
The sliding body moves in a straight line over a predetermined long stroke, moving through a gradual acceleration to an equidistant range, and then slowing down again to a stop. This eliminates shock and vibration at the beginning and end of the sliding body's movement. be done.

Moreover, while the roller is on the stationary part, the cam holds the sliding body in a stopped state via the roller even if the rotating shaft rotates a little. The sliding body can achieve high positioning accuracy even if it is not precisely controlled.

(Example) The present invention will be explained below according to the example shown in FIGS. 1 to 5.

Reference numeral 1 denotes a rotary shaft rotatably supported by a housing 4 via bearings 2 and 3, and 5 denotes a slider supported by a guide 6 so as to be slidable in the housing 4 in a direction orthogonal to the rotary shaft 1.

A rack 7 is formed in the sliding direction on the side surface facing the rotating shaft 1 of the slider 5, and rollers 10 and 11.
and 13 are arranged.

On the other hand, a pinion 14 corresponding to the rack 7 is integrally connected to the rotary shaft 1, and the pinion 14 meshes with the rack 7 to cause the slider 5 to move straight at a constant speed as the rotary shaft 1 rotates at a constant speed.

Further, the rotating shaft 1 is fed to the slider 5 via rollers 10, 11 or 12, 13 before and after the equidistant area of the slider 5, and is started to move through a gentle acceleration area to the equidistant area or Two plate cams 8 and 9 are connected in parallel to make the transition from an equidistant range through a gentle deceleration range to a stop.

These cams 8, 9 each have a true interior 15.degree. 16 (constituting a stop) and a shaped section 17.18, are axially symmetrical, and have rollers io, i1 or 12.
13 climbs onto the shaped parts 17 and 18, as the rotating shaft 1 rotates at a constant speed, the roller 11 or 1
3 while holding down roller 10 or 1 with the other shaped part 17.
It is designed to send to 2.

Incidentally, the cam-shaped portion 17.18 is connected to the roller 10.11 or 12.
．． 13, for example, the deformed constant velocity curve P in FIG.
The cam curve is set so that A dotted line Q in the figure shows the feed rate line of the slider 5 due to the rack 7 and the shaft 14.

When the rotating shaft 1 rotates at a constant speed in the direction of arrow A in the state shown in FIG.
When the slider 5 is lifted up, the slider 5 begins to be moved in the direction of arrow B via the rollers 10 and 11 as shown in FIG. 3, as described above, and the sending speed is gradually increased.

When the slider 5 shifts to a constant velocity configuration, the rack 7 and the pinion 14 engage with each other at a predetermined rotational angle position (in the rotational angle range shown in FIG. Thereafter, the slider 5 moves straight through a predetermined long stroke at a constant speed via the rack 7 and the pinion 14 as the rotary shaft 1 rotates at a constant speed.

When the rollers 12 and 13 are placed on the shaped portions 17 and 18 of the cams 8 and 9, the cams 8 and 9 act in a manner opposite to that shown in FIG. The rollers 12, 13 are sent out at a constant speed by a distance (including 15.1 times), but after this, the feeding speed is gradually reduced, and the slider 5 is stopped when the rollers 12, 13 move to the inner part 15.16.

Accordingly, as the rotating shaft 1 rotates at a constant speed, the slider 5 starts moving as shown in FIG. 5, slowly accelerates and shifts to a constant speed, and then gradually decelerates again and stops.

Note that when the rotating shaft 1 is reversely rotated, the slider 5 returns to its initial position through the same operation as described above.

By the way, according to this embodiment, a cam 8.9 and a roller 1 are used to gently accelerate and decelerate the slider 5 when it starts and stops.
Since 0.11, 12', and 13 are provided, shocks and vibrations at the beginning and end of the movement of the slider 5 can be eliminated.

Moreover, the cams 8, 9 have roller parts 1o, 11 or 12.1
As long as 3 is on the true inside 15.16, if rotation axis 1
Since the slider 5 is held in a stopped state by pinching the rollers 10, 11 or 12, 13 even if it rotates a little, the slider 5 can be positioned at a high level even if the drive start and stop positions of the rotating shaft 1 are not precisely controlled. Accuracy is obtained.

6 and 7 show another embodiment, in which the rotary shaft 1 is provided with flat grooved cams 20 and 21 in parallel in place of the plate cams 8 and 9.

One cam 20 has a spiral cam groove 22 on one side from the outer periphery toward the center, and the other cam 21 has a cam groove 22 on one side.
The backwash spiral cam groove 27 is symmetrical with respect to the axis R.
are formed respectively.

On the other hand, rollers 23 and 24 are provided at the front and rear portions of the slider 5, respectively, so as to correspond to the cams 20 and 21.
．． 26 and is disposed at the same height as the center of the cam 20.21.

The cam grooves 22.27 of the cams 20.21 are set to have a cam curve that gently accelerates and decelerates the slider 5 in the starting and stopping regions, as shown in FIG. However, cam groove 22.27
In the center of the cam 20, 21, arcuate portions (stop portions) 28, 29 are formed that are equidistant about the rotating shaft 1 within a predetermined rotation angle range. 'In the illustrated state, when the rotating shaft 1 rotates at a constant speed in the direction of arrow C, one of the cams 20 moves the roller 23 that has entered its cam groove 22 from the center to the outer periphery as the cam 20 rotates. The slider 5 is guided to the exit of the groove 22, and thereby the slider 5 is sent out through the O-ra 23 while being gently accelerated in the direction of arrow D.

When the slider 5 shifts to constant velocity, the rack 7 and the pinion 14 engage with each other at a predetermined rotation angle position, and at the same time, the roller 23 comes off the cam 20, and from then on the slider 5 moves to the rack 7.
Due to the action of the pinion 14, it moves straight at a constant speed.

Just before the rack 7 comes off the pinion 14, the roller 24
When the cam 21 is bitten by the cam groove 27 of the cam 21, the cam 21 moves the roller 24 deeper into the groove 27, decelerates the slider 5, and stops when the roller 27 reaches the arc portion 29. do.

Therefore, this embodiment also provides the same effects as described above.

Figure 8.9 further shows that similar effects can be obtained.
In another embodiment employing cylindrical grooved cams 30 and 31, rollers 32 and 33 are disposed at the front and rear of the slider 5, respectively, and the rollers 32 and 33 are disposed on the rotating shaft 1 within a predetermined rotation angle range. A cam 30 that meshes with the cam 30 and a cam 31 that also meshes with the roller 33
are connected.

The grooves 34.35 of the cam 30.31 have a twisting portion 36.37 that feeds out the roller 32 or 33 while gently accelerating or decelerating it as described above as the rotating shaft 1 rotates at a constant speed. Straight section 38 which clamps and holds 33.
It consists of 39.

In this case, since the slider 5 is disposed parallel to the rotating shaft 1, the teeth of the rack 7 and the pinion 14 are formed obliquely at the same angle of inclination.

(Effects of the Invention) In summary, according to the present invention, even if the drive of the rotating body on the input side is not precisely controlled, the sliding body on the output side can achieve high stopping accuracy, and the impact at the beginning and end of the movement can be reduced. Vibration can be eliminated, and therefore the reliability and durability of the device can be improved, and a device (for example, a servo motor) for controlling the drive of the rotating body can be eliminated, resulting in a cost reduction.

[Brief explanation of drawings]

Figure 1 is a schematic configuration diagram of the first embodiment, and Figure 2 is its X-X
Line sectional view, Fig. 3 is a cam operating stroke diagram, Fig. 4 is a cam characteristic diagram, Fig. 5 is a slider movement characteristic diagram, and Fig. 6 is a cam operation stroke diagram.
A schematic configuration diagram of the embodiment, FIG. 7 is a Y-Y sectional view thereof, and FIG.
The figure is a schematic configuration diagram of the third embodiment, and FIG. 9 is a partial Z-arrow diagram thereof. 1...Rotating axis, 5...Slider, 7...Rack,
8゜9.20. ．． 21.30.31.7Jmu, 10-1
3゜23,. 24, 32. 33...Roller, 1111
... Binion, 15.16 ... True interior, 17.18
...Shape part, 22.27...Cam groove, 28.29.
...Circular part, 36°37...Twisted part, 38.39...
・Straight section. Patent applicant Otsuka Cam Co., Ltd.

Claims (1)

[Claims] A rack is formed on the sliding body on the output side along the sliding direction, and rollers are provided at the front and rear of the sliding body, and the rack meshes with the rotating shaft on the input side and rotates at a constant speed of the rotating shaft. In addition, a pinion is provided to move the sliding body linearly at a constant speed, and the sliding body is fed through a roller before and after the serialization of the sliding body, and it is moved from startup to gradual acceleration and then to the regular serialization, or etc. From the series, we have provided a cam that allows the transition to stop after gradual deceleration, and that this cam has a stopping part that prevents the sliding body from being sent out in any direction via rollers in the starting and stopping areas of the sliding body. Features a linear feed mechanism.