JP2001200905A - Reciprocating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact reciprocating device capable of adjusting the reciprocating speed of a moving body at low cost without using a large and expensive servo motor having a speed control function. SOLUTION: One straight feeding shaft member 1 is formed of a round bar- like core 3 and an uneven spiral body 2a, and the feeding shaft member 1 is rotated for reciprocation around the core of the shaft 1 by a driving motor 10, and a pitch P of the spiral body 2a at each part of the feeding shaft member 1 is formed uneven by a reciprocating device formed by engaging a moving body 30, which is supported by a guide means 20 arranged in parallel with the feeding shaft member 1, with the spiral body 2a of the feeding shaft member 1 from the predetermined direction freely to be slid. The feeding shaft member 1 is rotated at a constant speed by the driving motor 10 so as to move the moving body 30 straight at a speed in proportion to the degree of the pitch P. With this structure, a compact constant speed rotary motor can be used for the driving motor 10 at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating moving device applied to a reciprocating feeding device such as an optical head in OA equipment and a reciprocating feeding mechanism such as a work table in a precision machine tool.

[0002]

2. Description of the Related Art As the reciprocating device, a belt type moving device using a timing belt and a servomotor (stepping motor) and a ball screw type moving device using a ball screw and a servomotor are generally used. The belt-type moving device reciprocates the moving object by locking the timing belt to a moving object that is linearly reciprocated in a fixed section, and reciprocating the timing belt on a constant track by a servomotor. The ball screw type moving device reciprocates an object to be moved by engaging a nut or the like fixed to the object to be moved with a thread or a screw groove of an equal pitch of the ball screw, and reciprocally rotating the ball screw by a servomotor. .

In these reciprocating devices, the reciprocating speed of a moving object in a fixed section is adjusted by automatically controlling the moving speed of the timing belt and the rotating speed of the ball screw by a speed control circuit built in the servomotor. Like that. For example, a moving object that reciprocates in a fixed section moves to one end of the fixed section, temporarily stops, and then starts moving in the opposite direction, but in order to reduce the influence of the inertial force received when the moving direction is reversed. In addition, the speed control circuit of the servomotor automatically controls the moving speed so that the moving speed gradually decreases when the moving object approaches the end of the fixed section. In applications where the moving object is moved at high speed in some sections of the fixed section and is moved at low speed in other sections, is it necessary to configure a servo motor speed control circuit to support this application? In addition, a command signal for speed change or the like is given to the speed control circuit.

[0004]

A reciprocating apparatus using a servomotor as described above can adjust the moving speed of a moving object reciprocating in a fixed section arbitrarily and with high accuracy.
Although used as a high-performance device for various applications, the speed control circuit required for the servomotor to variably adjust the moving speed of the moving object is expensive, and the entire motor is large. For this reason, the reciprocating device itself becomes expensive due to the servomotor, and it is difficult to reduce the cost of equipment products such as OA equipment incorporating the reciprocating device. When the moving speed of the moving object in the fixed section is variably adjusted by the servo motor, the position of the moving object in the entire section of the fixed section is detected one by one, and the detection signal is fed back to the servo motor speed control circuit. It is usual to prevent malfunction of speed control by doing
In this case, a detecting means such as an optical sensor for detecting the position of the moving object in the fixed section one by one, a protection circuit for preventing occurrence of a trouble due to a detection error of the detecting means, and the like are required. Are expensive and large in size.

[0005] A reciprocating device using a drive motor that only rotates reciprocally at a constant speed instead of the servomotor is also used in OA equipment and the like. This moving device does not have the above-mentioned problems associated with the servomotor because the driving motor that rotates at a constant speed is not equipped with a speed control circuit and thus is inexpensive and small. Since the moving speeds at the same time are the same, the content of work performed by reciprocating the moving object in a fixed section is narrowly limited, and there is a problem of lack of versatility. Further, when the moving object is moved at high speed in the fixed section, the moving object is suddenly stopped at the end of the fixed section, and a large inertial force acts on the moving object at the time of the sudden stop.

Therefore, the object of the present invention is to
It is an object of the present invention to provide an inexpensive and small reciprocating device that can freely adjust the reciprocating speed of a moving object without using a servomotor.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a feed shaft member having an uneven spiral body on the outer periphery and reciprocating around an axis, and reciprocating the feed shaft member at a fixed position. A drive motor for rotating, guide means arranged in parallel with the feed shaft member, and a guide end which is supported by the guide means so as to be able to reciprocate in the axial direction of the feed shaft member and extends from the guide means in the direction of the feed shaft member. In a reciprocating movement device having a moving body having an engagement means for slidably engaging a spiral body of a feed shaft member in the spiral direction, the pitch of the spiral body of the feed shaft member is made different in the axial direction of the feed shaft member. The moving speed of the moving body when the feed shaft member rotates at a constant speed is made proportional to the pitch of the spiral body (the invention of claim 1).

Here, the spiral body of the feed shaft member is a spiral projection or a spiral groove having a fixed width, and the pitch between adjacent portions of the spiral body at 360 ° is different. When the feed shaft member is reciprocally rotated by the drive motor, the moving body reciprocates in a ball screw manner through the engagement means between the spiral body and the moving body, and the moving speed at this time is the pitch of the spiral body of the feed shaft member and the feed shaft member. It is determined by the rotation speed of. When the feed shaft member is rotated at a constant speed, the moving speed of the moving body is determined variably only by the pitch of the spiral body. In this case, the drive motor for rotating the feed shaft member at a constant speed does not have a speed control circuit and is inexpensive. A small motor can be used.

[0009] Further, the engaging means of the moving body, which engages with the spiral body of the feed shaft member, is connected to the moving body in a direction in which the sliding resistance with the spiral body is reduced so as to be swingable. Item 2) is desirable in order to always stably maintain the frictional engagement state between the spiral body having the different pitches of the feed shaft members and the engagement means of the moving body.

Further, the spiral body of the feed shaft member is a strip wound around the outer periphery of the core rod at a different pitch in a convex shape (the invention of claim 3). It is desirable to manufacture a feed shaft member having the same at low cost.

[0011] Further, if the strip is wound around the outer periphery of the core rod of the feed shaft member so as to be movable in the axial direction of the feed shaft member, the pitch of the spiral body of the feed shaft member can be improved. Can be changed arbitrarily to change the moving speed of the moving body.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments will be described with reference to FIGS. The same or corresponding parts are denoted by the same reference symbols throughout the drawings.

The reciprocating device shown in one embodiment of FIG. 1 includes a linear feed shaft member 1, a drive motor 10 for reciprocatingly rotating the feed shaft member 1 around its axis, and a feed shaft member 1. Guide means 20 arranged in parallel with guide means 2
The moving body 30 is supported by being guided by the moving direction 0. A moving object (not shown) is connected to the moving body 30 and linearly reciprocated in a fixed section.

The feed shaft member 1 is formed, for example, by spirally winding a long strip 4a around the outer circumference of a core rod 3 which is a single linear metal round bar, and using the strip 4a to form an outer circumference of the core rod 3. Spiral body 2a
The pitch P of the spiral body 2a is made different as described later. The strips 4a are, for example, shown in FIGS.
The spiral component 5 is formed by spirally winding a strip-shaped steel plate having a constant width w and a constant thickness t as shown in FIG. As such a spiral component 5, a commercially available mini-spiral (trade name of Suncall Co., Ltd.) or the like can be applied, and by this application, the feed shaft member 1 can be manufactured at low cost. As shown in FIG.
The pitch P which is continuous in the axial direction of the strip-shaped strip 4a is gradually made different, and the core rod 3 is press-fitted into the spiral component 5 to fix the pitch P. Both ends of the core rod 3 without the spiral body 2a are rotatably supported by the bearings 6, 6, and the bearing 6,
6 is fixed to a flat fixed frame 7, and the feed shaft member 1 is supported in parallel with the fixed frame 7.

The drive motor 10 is supported by the fixed frame 7 and connected to one end of the core rod 3 of the feed shaft member 1 via a speed reduction mechanism 11. The drive motor 10 rotates the feed shaft member 1 at a constant speed in both the forward and reverse directions. Therefore, an inexpensive and small motor without a speed control circuit or the like is used. It should be noted that a servomotor such as a conventional reciprocating device can be applied to the drive motor 10, but this application is unnecessary and uneconomical for the reasons described below.

The guide means 20 is a guide rod, a guide groove, a guide rail or the like parallel to the feed shaft member 1, and FIG. 1 shows one linear guide rod 20. The moving body 30 is fitted to the guide rod 20 so as to be slidable in the axial direction. Both ends of the guide rod 20 are fixed to the support 21, and the support 21 is fixed to the fixed frame 7.

The moving body 30 includes a cylindrical slider portion 31 slidably fitted to the guide rod 20 and a connecting portion extending from the slider portion 31 toward the feed shaft member 1 integrally with the slider portion 31. 32 and an engaging means 33 connected to the tip of the connecting portion 32. The engagement means 33 engages a part of the spiral body 2a of the feed shaft member 1 so as to be slidable in the spiral direction of the spiral body 2a, and the spiral body 2a is a strip-shaped strip 4a.
In this case, the engaging means 33 is a bifurcated claw member which clamps the strip 4a of the band plate in the plate thickness direction. The engaging means 33 engages with the spiral body 4a of the feed shaft member 1 in the radial direction of the axis of the feed shaft member 1 and from the fixed direction in which the guide rod 20 exists. When the feed shaft member 1 rotates, the spiral body 4a rotates while being frictionally engaged with the engaging means 33, and moves the engaging means 33 in the axial direction of the feed shaft member 1, whereby the moving body 30 is moved by the axial movement. It is moved linearly by being guided by the guide rod 20.

The pitch P of the spiral body 2a of the feed shaft member 1 is
For example, as shown in FIG. 1, the pitch Pa at the center of the feed shaft member 1 is maximum, the pitch gradually decreases from the center to both ends, and the pitch Pb at both ends is minimized. It is. As shown by the solid line in FIG. 1, in a state where the engaging means 33 of the moving body 30 is engaged with the spiral body 2 a at the center of the feed shaft member 1, the feed shaft member 1 is When the mobile unit 30 is rotated at a constant speed (in the direction indicated by the solid line arrow in FIG. 1), the moving body 30 starts linearly moving in the right direction in FIG. The moving speed of the moving body 30 at the start of movement is determined by the feed shaft member 1.
Is constant in proportion to the pitch Pa of the spiral 2a with which the engaging means 33 is engaged, and therefore the moving speed at the start of the movement is the maximum, and the pitch P becomes smaller as the moving starts, and the moving speed becomes smaller. Gradually decreases, and when the moving body 30 moves to one end of the feed shaft member 1, the minimum pitch P
The minimum moving speed is obtained by b. When the moving body 30 is at the position shown by the solid line in FIG.
(In the direction of the dashed arrow in FIG. 1), the moving body 30 linearly moves in a speed change pattern in which the moving body 30 starts at the left in FIG.

As described above, the feed shaft member 1 is
When the moving body 30 is reciprocated at a constant speed of 0, the moving speed of the moving body 30 can be arbitrarily changed so that the moving body 30 moves at a high speed at the center of the feed shaft member 1 and moves at a low speed at both ends. When the moving body 30 moves to a fixed position near both ends of the guide rod 20, it is desirable to install switches 22, 22 such as limit switches for detecting the position and outputting an electric signal on the fixed frame 7. . The rotation of the feed shaft member 1 is temporarily stopped by the detection signals of the switches 22 and 22, the linear movement of the moving body 30 is temporarily stopped, and then the moving direction is reversed.

Such a temporary stop of the moving body 30 can be performed smoothly without receiving a large inertial force because the moving speed immediately before stopping is the minimum speed at the minimum pitch Pb. In addition, since the moving body 30 can be moved at a high speed at the central portion of the feed shaft member 1, various operations can be performed at a high speed with the moving object that reciprocates linearly with the moving body 30. Further, the drive motor 10 as a drive source for moving the moving body 30 by changing the speed only rotates at a constant speed, so that an inexpensive and small motor having a rotation on / off switch circuit can be used. In addition, moving body 3
The moving speed at each position within a moving section (corresponding to a fixed section between a pair of switches 22, 22) determined between both ends of the guide rod 20 is the spiral body 2 of the feed shaft member 1.
Since the pitch P is determined by the pitch P, it is not necessary to detect the position of the moving body 30 in every section of the moving section, and the moving speed of the moving body 30 in the whole moving section can be controlled with high accuracy.

Next, more specific embodiments of the present invention will be described in order with reference to the drawings.

As shown in the embodiment of FIG. 1, when the feed shaft member 1 is configured by spirally winding a strip-shaped strip 4a around a round rod-shaped core rod 3 at different pitches, FIG. As shown in the cross-sectional view, the strip-shaped strip 4a is inclined with respect to the outer periphery of the core rod 3, and the inclination angle θ is proportional to the pitch of the strip 4a. Therefore, the engaging means 33 of the moving body 30 to be engaged with the strip 4a
To the connecting portion 32 of the moving body 30 so as to be swingable in the axial direction of the feed shaft member 1 so as to follow a change in the inclination angle θ of the strip 4a with which the engaging means 33 engages. Be inclined. In this case, the engaging means 33 is connected to the strip 4a.
Is always engaged in a stable state parallel to the strips 4a even if the inclination angle θ changes, and slides with low frictional resistance without being stuck to the strips 4a. In addition, by installing the engagement means 33 so as to be able to swing and swing, the feed shaft member 1 is provided.
Can be constituted by a strip-shaped strip 4a, that is, a commercially available and inexpensive spiral part 5 shown in FIG.

FIGS. 4A and 4B show a modification of the engaging means 33, in which a pair of rollers 34, 34 is attached to a bifurcated engaging means 33 which sandwiches a strip-shaped strip 4a. The pair of rollers 34, 34 are rotatably assembled so as to roll on both surfaces of the strip 4a. Thus, the rollers 34,
By slidably moving the engagement means 33 along the strip 4a via 34, a smoother engagement between the two can be ensured.

The embodiment shown in FIG. 5 is similar to the embodiment shown in FIG.
A spiral body 2a of a convex shape is formed by winding a strip 4b of a round rod-shaped wire around the outer periphery of the wire at a different pitch. In this case as well, the engagement means 33 may be slidably engaged with the strip 4b of the round rod wire so as to sandwich the engagement means 33. A commercially available and inexpensive spiral spring wire can be applied to the spiral strip 4b of such a round rod.

The embodiment shown in FIG. 6 shows an example of a change in the shape of the spiral 2b of the feed shaft member 1. The spiral 2b is formed in a spiral groove formed by spirally cutting the outer periphery of a cylindrical core rod 3. It is. The spiral groove 2b has a constant width and a pitch P between the grooves.
Are different. The engagement means 33 of the moving body 30 with the spiral groove 2b integrally has a projection 33 'which is fitted into the spiral groove 2b and slidably frictionally engages with both side walls of the spiral groove 2b. The formation of such a spiral groove 2b may be performed by NC control in the manner of ordinary thread groove cutting.

The embodiment shown in FIGS. 7A and 7B is a modification of the embodiment shown in FIG. That is, when the strip-shaped strip 4a of the embodiment of FIG. 2 is wound around the outer circumference of the core rod 3 at a different pitch P, the strip plate-shaped strip 4a is fixed to the core rod 3 as it is. The embodiment shown in FIG. 7 uses the elasticity of the strip 4a to elastically couple to the outer periphery of the core rod 3 so as to be movable in the axial direction. 7 (A) shows a pitch state similar to that of FIG. 2, and the pitch is changed by moving the strip 4a in the axial direction while being in elastic contact with the core rod 3. FIG. 7 (B). As described above, the pitch P of the spiral body 2a in one feed shaft member 1 can be arbitrarily changed, so that the moving body 30 can be reciprocated at one of the feed shaft members 1 at more various moving speeds. In addition, the moving speed of the moving body 30 can be changed at the stage of using the reciprocating device.

FIGS. 8 to 10 show modifications of the pitch form of the spiral body 2a in one feed shaft member 1. FIG. That is, the feed shaft member 1 shown in FIG.
In FIG. 8, the pitch Pc at the center of the feed shaft member 1 is minimized, and the pitch Pd at both ends is maximized, while the pitch form is such that a is maximized and the pitch Pb is minimized at both ends. . Further, the feed shaft member 1 of FIG. 9 minimizes the pitch Pe at one end, enlarges the pitch toward the other end, and maximizes the pitch Pf at the other end. FIG. 8
The pitch form of the feed shaft member 1 in FIG. 9 and FIG. 9 is determined according to a request for the moving speed in a fixed section of the moving body 30. Further, such a selection of the pitch form can be executed by one feed shaft member 1 if the pitch of the strip 4a on the core rod 3 is allowed to change as in the embodiment of FIG.

In the embodiment shown in FIG. 10, a long strip 4a is spirally wound around the outer periphery of one half of the core rod 3 in the longitudinal direction, and then the strip 4a is continuously connected. Is wound around the outer periphery of the other half of the core bar 3 with the helical direction reversed to form helical bodies 2a ', 2a "having helical directions opposite to each other from the center of the core rod 3 to both sides. Independent 2
The pitch forms of the spiral bodies 2a 'and 2a "are such that the pitch Pg at the center of the feed shaft member 1 is small and the pitch Ph at both ends is large. Is done. When the feed shaft member 1 is reciprocated, the pair of moving bodies 30 ′ and 30 ″ move at the same time in the opposite directions at the same speed and move at the same time.

[0029]

According to the present invention, when the feed shaft member is reciprocated at a constant speed by the drive motor, the moving body reciprocates at different speeds according to the different pitches of the spirals of the feed shaft member. It is possible to control the moving speed such as moving the moving body at a desired section at a high speed or moving the moving body at a predetermined stop position at a low speed and stopping only by the pitch of the spiral body of the feed shaft member. It is possible to provide a reciprocating device having a high performance capable of setting a moving speed and having excellent versatility. In addition, since the moving speed of the moving body can be controlled by rotating the feed shaft member at a constant speed, a simple, inexpensive, and small-sized motor that does not include a speed control circuit in the drive motor that reciprocates the feed shaft member is provided. Applicable, it is easy to reduce the cost and size of the reciprocating device.

Further, the spiral body of the feed shaft member is formed of a convex strip, and the engaging means of the moving body is engaged with this strip so as to swing and swing, thereby engaging with the spiral strip. The combining means slides smoothly without being entangled, and the reciprocating movement of the moving body is stabilized.

Further, by forming a spiral body by winding a strip around the outer periphery of the core rod, it becomes easy to manufacture feed shaft members having different pitches, and it is possible to reduce the manufacturing cost.

Further, by winding the strip around the outer periphery of the core rod such that the pitch can be changed, it is possible to change the moving speed of the moving body with one feed shaft member, thereby expanding the versatility of the reciprocating moving device. And added value can be increased.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a reciprocating device according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of the apparatus in FIG. 1;

FIG. 3 is an exploded perspective view of a feed shaft member in the apparatus in FIG.

FIG. 4A is a partial sectional view showing a second embodiment of the present invention, and FIG. 4B is a sectional view taken along line XX of FIG. 4A.

FIG. 5 is a partial plan view including a partial cross section showing a third embodiment of the present invention.

FIG. 6 is a partial plan view including a partial cross section showing a fourth embodiment of the present invention.

7A is a partial cross-sectional view showing a fifth embodiment of the present invention, and FIG. 7B is a partial cross-sectional view when the pitch is changed by moving the strip shown in FIG. 7A.

FIG. 8 is a partial plan view of a main part showing a sixth embodiment of the present invention.

FIG. 9 is a partial plan view of a main part showing a seventh embodiment of the present invention.

FIG. 10 is a partial plan view of a main part showing an eighth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Feed shaft member 2a Spiral 2b Spiral P Spiral pitch 3 Core rod 4a Strip (strip-shaped) 4b Strip (round rod) 5 Spiral component 10 Drive motor 20 Guide means, guide rod 30 Moving body 33 Engaging means

Claims (5)

[Claims] 1. A feed shaft member having an uneven spiral body on the outer periphery and reciprocatingly rotating around an axis, a drive motor for reciprocatingly rotating the feed shaft member at a fixed position, and a feed shaft member arranged in parallel with the feed shaft member. The guide means is supported by the guide means so as to be able to reciprocate in the axial direction of the feed shaft member, and the tip extending in the direction of the feed shaft member from the guide means is slidable in the spiral direction of the spiral body of the feed shaft member. In a reciprocating movement device provided with a moving body having an engaging means for engaging, the pitch of the spiral body of the feed shaft member is made different in the axial direction of the feed shaft member, so that the moving body at the time of constant speed rotation of the feed shaft member is changed. A reciprocating device wherein the moving speed is proportional to the pitch of the spiral. 2. A moving body engaging means for engaging with a spiral body of the feed shaft member is connected to the moving body so as to be swingable in a direction to reduce sliding resistance with the spiral body. The reciprocating device according to claim 1, wherein 3. The reciprocating moving device according to claim 1, wherein the spiral body of the feed shaft member is a strip wound around the outer periphery of the core rod at a different pitch and convexly. 4. The reciprocating device according to claim 3, wherein a strip is wound around the outer periphery of the core rod of the feed shaft member so as to be movable in the axial direction of the feed shaft member. 5. The reciprocating movement according to claim 3, wherein the strip is a spiral part formed by spirally bending a long strip having a constant width and a constant thickness in a width direction. apparatus.