RU2707156C1 - Method for stabilization of movement along gear rack and device for its implementation - Google Patents

Abstract

FIELD: printing industry.SUBSTANCE: invention relates to equipment in which toothed rack motion is used and can be used in printing devices on large-format industrial printers. In method of stabilization of movement along gear rack, rack and linear guide are fixed on fixed part, and for movement along rack there is used motor, which rotates gear wheel located on movable part, note here that at least two movable carriages are arranged on linear guide to be fastened to moving part. Linear guide is attached in parallel along the rack on the fixed part, and to the linear perpendicularly linear part of the movable part, a vertical linear guide is attached, on which the stabilizing carriage is vertically displaced up and down, a plate is attached to the stabilizing carriage, through which the shaft of the motor rotating the gear wheel is passed, wherein in the zone located above the engine shaft to the movable part the bracket is attached, through the hole in which the spring tensioner is passed, which by the other end is connected to the ledge fixed on the plate.EFFECT: higher reliability of the device and higher accuracy of operation.6 cl, 2 dwg

Description

The invention relates to equipment that uses movement along a rack and can find application in printing devices for large-format industrial printers (plotters), robots and machine tools with programmed control.

When carrying out rectilinear motion (along linear guides) in printers, computer-controlled machines and robotic systems, conversion of the rotation of the engine gear into its linear movement relative to the gear rack is used. The amount of movement is set by stepper or servomotors. The accuracy of movement along the length of the rack depends, to a large extent, on the relative position of the gear and the gear rack.

The technical problem of known machines and equipment, and especially large-format printers, is the change in the relative position of the gear and the gear rack at horizontal displacements, which varies depending on the curvature of the bearing surface of the rack and the forces that are applied to the gear wheel. To stabilize the accuracy of movement along the rack to the gear wheel, preliminary forces are applied that press the wheel to the rack. The gear and rack have the following key features:

1. A large gear ratio - for one revolution of the gear wheel, the rack moves to the length of the initial circumference of this wheel. Therefore, a pair of gear-rack is convenient to use in the drive of the main movement and in the drive of various auxiliary movements.

2. The unevenness of the gear ratio due to the large influence of gear errors on the speed of the rack. It is especially difficult to provide a pair of gear-rack uniformity of slow movements in the feed drive of high-precision machine tools and CNC machines.

3. The lack of self-braking makes it difficult to use a gear gear-rack for the vertical movement of machine components.

4. Low friction losses and high transmission efficiency justify its use in the drive of the main movement of longitudinal planing and mortising machines when transmitting significant power.

5. The manufacturability of the manufacture and assembly of a pair of gear wheels-racks determines its low cost, which leads to a fairly widespread use of this pair in auxiliary devices with low requirements for accuracy. The rack and pinion gear consists of a gear and a rack. The transmission is carried out with straight, oblique and chevron teeth and serves to convert the rotational motion to translational and vice versa. When the rack is stationary, the gear wheel rolls along the rack, i.e. makes rotational and translational motion.

The wheel-to-rail systems known in the technology of large format printers are technically complex and have many electronic components. This is fraught with the fact that the failure of any micro-node or the failure of the alignment of one of the settings leads to a violation of the stable operation of the system and a decrease in print quality.

In addition, the movement along the gear rack has a noisy gear operation.

It is known (see https://darxton.ru/wiki-article/mify-o-reechnoy-peredache/) that metalworking technologies have made significant progress in recent years, which has resulted in a radical increase in the precision of manufacturing transmission elements - gear racks and gears. At present, rails of almost all accuracy classes according to JIS are produced, up to 1. And also there are backlash-free rack and pinion gears, etc. At present, the rack and pinion transmission as a whole is not inferior in positioning accuracy to the drive screws, and in most cases it surpasses the belt drive.

The cremallera has a theoretical distance from the center of the gear to the dividing line of the rack, at which the gearing works in an optimal way. By pressing the gear to the rack, it is possible to reduce the play, but this will affect the meshing of the teeth, which can lead to increased wear and abrasion of the gear. A large backlash indicates a low transmission quality. The best way to reduce backlash is to use a high-quality rail and gears with a high level of performance, and also to improve the quality of the mutual assembly. A split or double gear will help to completely eliminate play.

In some cases, the play can be completely eliminated by using special preloaded nuts. However, rack and pinion transmission can also be accurate and repeatable. In cases of using hardened rails, which are then hardened and then brought into tolerances, it is similarly possible to achieve small backlash and pitch errors. And the use of half or double gears allows you to completely eliminate the backlash. And in long and massive CNC axes, such as cutting machines, the rack-and-pinion transmission actually significantly exceeds the ball screw (ball screw pair), which is limited in length due to the sagging and vibration of the screw, as well as in speed of movement.

In heavy-duty applications, the classic gear train is significantly superior to the roller gear - the latter lacks rigidity and load capacity.

The closest analogue is Monorail BZ profile rail guides with a rail on the rail (published: 07/10/2017., See: http://www.promshop.info/cataloguespdf/MONORAIL_BZ.pdf). They used the pinion of the gear to the rack by means of movable carriages.

In the prototype, the method of stabilizing the movement on the gear rack is based on the fact that the gear rack and the guide are mounted on the fixed part, and to move the rack using an engine that rotates the gear located on the moving part, at least two movable carriages are placed on the guide, which are attached to the movable part.

Inaccuracies in the installation of structural elements that lead to inconstancy of the gap between the gear rack by the gear wheel cause inaccuracies in movements (unequal length of movement by one revolution of the gear in different places of the gear rack).

A measure of the fight against this phenomenon can be the pressing of the gear to the gear rack, which causes both an increase in the accuracy of movement and the running-in of the rack by the hardened gear. But pressing the gear to the gear rack, although it is possible to reduce the backlash, but this will affect the engagement of the teeth, which can lead to increased wear and wear of the gear.

Therefore, the main technical problem of the prototype is the dependence on the strong pinion of the gear to the gear rack, which affects the meshing of the teeth and leads to increased wear and wear of the gear.

On the other hand, the need to use an expensive and technologically difficult to manufacture high-quality gear rack and pinion with a high level of performance, as well as improving the quality of their mutual mounting, or using a split or double gear, all this greatly complicates the design, makes it technologically complex and dependent on each node of the system, where the failure of any small part or its wear, leads to a loss of accuracy of movement along the gear rack of the entire mobile system.

The objective of the claimed solution is to find a balanced technical solution that uses inexpensive gear racks and gears, but at the same time provides optimal play and optimal pressure of the gear to the gear rack, which maintains high transmission quality and does not cause wear and tear of the gear. Thus, the task is posed: to eliminate the need for expensive and technologically difficult to manufacture high-quality gear racks and gears with a high level of performance, to eliminate the need for the quality of their mutual mounting, the use of split or double gears.

The technical result is to increase and stabilize the accuracy of movement along the gear rack, reduce the noise of the gearing, increase the service life of the gear rack and gear when using gear racks and gears of the middle accuracy class. In addition, jamming is prevented and the protruding sections of the rack are counted.

The specified technical result is achieved due to the fact that the claimed method of stabilizing the movement of the gear rack, in which the gear rack and linear guide are mounted on a fixed part, and to move along the rack using an engine that rotates the gear located on the moving part, and on the linear at least two movable carriages that are attached to the movable part, characterized in that the linear guide is mounted parallel to the rack on the fixed part, and a vertical linear guide is mounted on the movable part perpendicular to the linear guide, on which a stabilizing carriage is mounted vertically up and down, a plate is fastened to the stabilizing carriage, through which the shaft of the motor rotating the gear wheel is passed, while in the area located above the motor shaft to the movable parts fasten the bracket, through the hole in which the spring tensioner is passed, which at the other end is connected to the protrusion mounted on the plate.

Preferably, the fixed part is in the form of a bed.

Preferably, at the point of greatest tooth engagement, the spring tension is reset to zero by an adjustable limiter, which is passed through the bracket and end abutted to the upper part of the motor rotating the gear wheel, or to the plate on which it is fixed.

Also claimed is a device for stabilizing movement along a gear rack, in which the gear rack and linear guide are fixed to the fixed part, and the motor is connected to the movable part, coupled to the gear by the moment of rotation, and the movable carriages mounted on the linear guide fixed to the movable part, characterized the fact that the linear guide is fixed in parallel along the gear rack on the fixed part, and at least two carriages mounted on the linear direction are fixed on the moving part a vertical linear guide fixed to the movable part perpendicular to the linear guide, on which a stabilizing carriage is mounted with vertical displacement up and down, to which a plate is fixed, through which the shaft of the engine rotating the gear wheel is passed, and to the movable part in the area located a bracket is mounted above the shaft of the engine rotating the gear wheel, having an opening through which a spring tensioner is passed, which is connected to the protrusion at the other end captive on the plate.

Preferably, the fixed portion is a bed.

Preferably, an adjustable stop is passed through the bracket, which end rests on the upper part of the motor housing rotating the gear wheel, or the plate on which it is fixed.

Brief Description of the Drawings

In FIG. 1 shows a device of a system for stabilizing movement along a gear rack (end view).

In FIG. 2 shows a device of a system for stabilizing movement along a gear rack (sectional side view).

In the drawings: 1 - moving part, 2 - linear guide carriage, 3 - linear guide of the moving part, 4 - bed, 5 - gear rack, 6 - gear wheel, 7 - vertical linear guide of the stabilization system, 8 - stabilizing carriage of a vertical linear guide , 9 - engine, 10 - spring, 11 - spring tensioner, 12 - limiter, 13 - motor shaft, 14 - bracket, 15 - plate.

The implementation of the invention

The claimed method for stabilizing the movement along a gear rack is implemented as shown in FIG. 1, FIG. 2. The gear rack 5 and the linear guide 3 are mounted on a fixed part, which may be, for example, a frame 4.

At least two movable carriages 2 are placed on the rail, which are attached to the movable part 1. The movable part is performed, for example, in the form of a set of connected plates to which these or other nodes are attached.

To move the rack 5 use the engine 9, which rotates the gear 6 located on the movable part 1.

What is new is that the linear guide 3 is fixed in parallel along the gear rack 5 on the fixed part. A vertical linear guide 7 is mounted to the movable part 1 perpendicular to the linear guide 3, on which a stabilizing carriage 8 is mounted with vertical displacement up and down. A plate 15 is mounted on the stabilizing carriage 8, on which the motor and gearbox or motor are mounted (if you do not need much effort ), and through the plate 15 pass the shaft of the engine 13 or the shaft of the gearbox rotating the gear 6. In this case, in the area located above the shaft 13 of the engine 9, a bracket 14 is fixed to the movable part 1, through which an aperture spring tensioner allowed October 11, which is connected to the other end of the protrusion fixed to the plate 15.

The principle of stabilization of motion on the gear rack is as follows.

Due to the imperfection of the plane of the rails of the linear guide and the rack, the engagement of the gear and the rack will be different in length.

In conventional known systems as in the prototype, the pressure of the gear to the gear rack is provided by the movements of the carriages along the horizontal linear guides, which are mounted in parallel along the gear rack on the fixed part.

As previously mentioned, by pinching the gear to the rack, it is possible to reduce the play, but this will affect the meshing of the teeth, which can lead to increased wear and wear of the gear.

On the other hand, the objective of the claimed solution is to eliminate the need for expensive and technologically difficult to manufacture high-quality gear racks and gears with a high level of performance, to eliminate the need for the quality of their mutual assembly, the use of split or double gears.

Therefore, to ensure the balance of stabilization of movement along the gear rack, it is necessary to compensate for the backlash mechanically.

The gear rack 5 and the linear guide 3 are fixed on the fixed part parallel to each other indented from each other. This weakens the strong pressure of the gear of the gear wheel 6 to the gear rack 5 using the carriages 2.

On the other hand, the weight of the engine 9 presses against the shaft 13. The shaft, in turn, presses against the plate 15 through which it is passed. The weakening of the clamping of the gear to the gear rack leads to the appearance of play, from a different length of engagement of the gear wheel and gear rack. Backlash is gently eliminated by the work of the system of stabilization of movement along the gear rack. This principle is based on the fact that the vertical vibrations of the movable part 1, on which the engine is mounted, are damped due to the movements of the stabilizing carriage 8 up and down along the vertical linear guide 7.

A dynamic change in the position of the stabilizing carriage is provided by the tension of the spring 10 and the adjustment of the force of its tension. The clamping force is created by a stretched spring 10, the tension of which is regulated by the tensioning bolt of the tensioner 11, but in places of the smallest (greatest) engagement it can be zeroed by focusing on the limiter 12, which is passed through the bracket 14 and end abut against the upper part of the motor housing 9, rotating the gear wheel 6 , or into the plate 15 on which it is fixed.

Thus, the claimed solution provides a system for stabilizing the movement of the gear rack, eliminating the load on the transmission and backlash with irregularities in the relative position of the gear and the gear rack. The floating suspension of the stabilization mechanism presses the gear to the rack with the necessary effort, choosing the backlash. Thus, the noise level of the gearing is reduced, the accuracy of movement is maintained, and the service life of the rack and pinion is significantly increased.

On the other hand, due to the elimination of backlash, stable movement along the gear rack is ensured, which prevents jamming and takes into account the protruding sections of the gear rack and its running-in. The running-in of the rack by the gear wheel, being virtually an unavoidable negative phenomenon for any gear transmission, at the same time in the initial period of operation reduces the inaccuracies of the assembly of the structure.

Claims (6)

1. A method of stabilizing movement along a rack, in which the rack and linear guide are mounted on a fixed part, and to move along the rack using an engine that rotates the gear located on the moving part, at least two movable carriages are placed on the linear guide which are attached to the movable part, characterized in that the linear guide is mounted parallel to the gear rack on the fixed part, and a vert is attached to the movable part perpendicular to the linear guide a linear linear guide, on which a stabilizing carriage is mounted with vertical displacement up and down, a plate is fastened to the stabilizing carriage, through which the shaft of the engine rotating the gear wheel is passed, while in the region located above the motor shaft, the bracket is fixed to the movable part, through a hole in which the spring tensioner is passed, which is connected to the protrusion mounted on the plate at the other end. 2. The method according to p. 1, characterized in that the fixed part is performed in the form of a bed. 3. The method according to p. 1 or p. 2, characterized in that in the place of the greatest tooth engagement, the spring tension is reset to zero by an adjustable limiter, which is passed through the bracket and end rests on the upper part of the motor rotating the gear wheel, or in the plate, on which it is fixed. 4. Device for stabilizing movement along a gear rack, in which the gear rack and linear guide are fixed on the fixed part, and the motor is fixed on the moving part, which is connected by the moment of rotation with the gear wheel, and on the linear guide mounted movable carriages fixed to the movable part, characterized the fact that the linear guide is fixed in parallel along the gear rack on the fixed part, and at least two carriages mounted on the linear guide are fixed on the movable part, with a vertical linear guide is fixed on the movable part perpendicular to the linear guide, on which a stabilizing carriage is mounted with vertical displacement up and down, to which a plate is fixed, through which the shaft of the motor rotating the gear wheel is passed, and to the movable part in the area located above the shaft a motor rotating a gear wheel, a bracket is fixed having an opening through which a spring tensioner is passed, which is connected at the other end to a protrusion fixed to the Stine. 5. The device according to p. 4, characterized in that the fixed part is a bed. 6. The device according to p. 4 or 5, characterized in that an adjustable stop is passed through the bracket, which end rests on the upper part of the motor housing rotating the gear wheel, or the plate on which it is fixed.

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