CN201304583Y - Reverse gap elimination and micro-adjusting mechanism of rotary worktable precision transmission system - Google Patents

Abstract

The utility model relates to a reverse clearance elimination and micro-adjustment mechanism of a precision transmission system of a rotary table in the field of advanced manufacturing technology, including: Tightening screw, fine-tuning screw hole, dial, wherein: the waist hole is set on the left lobe of the double-lobe gear, the left half shaft of the eccentric shaft is sleeved in the waist hole, the right half shaft of the eccentric shaft is sleeved in the right lobe of the double-lobe gear, the fine-tuning screw The hole is arranged at the right end of the eccentric shaft, and the clamping screw is screwed in from the left side of the double-lobe gear to connect the left lobe of the double-lobe gear with the right lobe of the double-lobe gear, and the dial is fixed on the right end of the right lobe of the double-lobe gear. The utility model realizes the adjustment and clamping of the gap and the pre-pressure through the adjustment of the eccentric shaft and the clamping of the thread, and meets the high-precision requirements of the five-axis machine tool.

Description

Elimination of Backlash in the Precision Drive System of Rotary Table and Its Micro-adjustment Mechanism

technical field

The utility model relates to a device in the field of advanced manufacturing technology, in particular to a reverse clearance elimination and micro-adjustment mechanism of a precision transmission system of a rotary table.

Background technique

Because the feed system of CNC machine tools is often in the state of frequent change of load, the backlash of the tooth will cause the machining error when the feed is reversed, and produce a reverse dead zone, which will affect the machining accuracy. Therefore, measures must be taken to eliminate the backlash in the gear transmission .

Through literature retrieval of prior art, it is found that Wu Liqun published an article "Methods for Eliminating Gear Transmission Gap" in the fifth issue of "Machine Tool and Hydraulic Pressure" in 2005, P187-P188. This article mainly introduces spur gear transmission, helical The elimination (or reduction) method of backlash in gear transmission, bevel gear transmission, etc., and the characteristics of the relevant methods are introduced. Among them, the shim adjustment method in the helical gear transmission is: the wide gear meshes with two thin gears with the same number of teeth at the same time, and the thin gears are connected to the shaft through a flat key, and there is no relative rotation between them. A gasket with a thickness of t is added between the helical gears. Tighten with a nut to make the helix of the two gears misaligned, and then the two tooth surfaces are respectively close to the tooth surfaces of the wide gear to eliminate the gap. Its disadvantage is that for different gear clearances, gaskets of different thicknesses need to be used, the adjustment is cumbersome, and the preload cannot be adjusted. There is also an axial compression spring adjustment method in the article. The helical gear is slipped on the shaft with a key, and there is no relative rotation between them. The helical gear meshes with the wide gear at the same time, and the nut adjusts the butterfly spring so that the tooth sides of the gear are respectively close to the left and right sides of the tooth groove of the wide gear, eliminating the gap. This method can automatically compensate the gap, but there is no preload and the rigidity is poor.

Utility model content

The purpose of this utility model is to aim at the deficiencies of the prior art, to provide a mechanism for eliminating the backlash and micro-adjustment of the precision transmission system of the rotary table, through the adjustment of the eccentric shaft and the clamping of the thread, the adjustment of the gap and the pre-pressure can be realized And clamping, to meet the high-precision requirements of five-axis machine tools.

The utility model is realized through the following technical solutions, including: eccentric shaft, left lobe of double lobe gear, right lobe of double lobe gear, waist hole, clamping screw, fine-tuning screw hole, dial. The connection relationship is: the waist hole is opened on the left lobe of the double-lobe gear, the left half shaft of the eccentric shaft is sleeved in the waist hole, the right half shaft of the eccentric shaft is sleeved in the right lobe of the double-lobe gear, the fine-tuning screw hole is opened on the right end of the eccentric shaft, and the clip The tightening screw is screwed in from the left side of the double-lobe gear, and the left lobe of the double-lobe gear and the right lobe of the double-lobe gear are connected together and can be tightened, and the dial is fixed on the right end of the right lobe of the double-lobe gear.

The principle of the utility model is that when the right fine-tuning screw is rotated, the eccentric shaft rotates slightly, the left shaft swings and slides in the hole, drives the left gear to rotate slightly, and the two-lobed gears on the right side have a relative angle Displacement, when they mesh with wide gears, eliminates gear backlash. The design of the eccentric shaft should ensure that the contact surface with the gear is in a self-locking state of friction, so that the gear clearance and pre-pressure can be adjusted accurately.

The utility model realizes the adjustment and clamping of the gap and the pre-pressure through the adjustment of the eccentric shaft and the clamping of the thread, and meets the high-precision requirements of the five-axis machine tool. The utility model can accurately eliminate the gap under the condition of known gap, and obtain the required pre-clamping force through thread clamping.

Description of drawings

Fig. 1 is the structural representation of the utility model

Figure 2 is a schematic diagram of angle adjustment

Detailed ways

Below in conjunction with accompanying drawing the embodiment of the present utility model is described in detail: present embodiment is carried out under the premise of technical solution of the present utility model, has provided detailed embodiment and concrete operation process, but protection scope of the present utility model It is not limited to the following examples.

As shown in Figure 1, the elimination of the backlash and the micro-adjustment mechanism of the precision transmission system of the rotary table involved in this embodiment include: the left lobe 1 of the double-lobe gear, the right lobe 2 of the double-lobe gear, the fine-tuning screw hole 3, the eccentric Shaft right half shaft 4, clamping screw 5, eccentric shaft left half shaft 6, waist hole 7, dial 8. The connection relationship is: the waist hole 7 is set on the left lobe 1 of the double-lobe gear, the left half shaft of the eccentric shaft 6 is set in the waist hole 7, the right half shaft of the eccentric shaft 4 is set on the right lobe 1 of the double-lobe gear, and the fine-tuning screw hole 3 is opened. At the right end 4 of the eccentric shaft, the dial 8 is fixed on the right end of the right lobe 2 of the double-lobe gear, and the clamping screw 5 is screwed in from the left lobe 1 of the double-lobe gear, and the left lobe 1 of the double-lobe gear is connected with the right lobe 2 of the double-lobe gear. together and can be tightened.

In this embodiment, the fine-tuning screw hole 3 is a fine-tuning inner hexagonal screw hole.

The specific work and use process of this embodiment: After the user measures the gear backlash, calculate the required rotation angle of the fine-tuning screw hole 3, and turn the fine-tuning inner hexagonal screw hole 3 with a wrench according to the angle scale on the dial 8, Make it reach the required angle, at this time, the right half shaft 4 of the eccentric shaft rotates slightly, drives the left half shaft 6 to swing, and slides down in the middle of the waist hole 7, so that the left lobe 1 of the double lobe gear rotates slightly, and the double lobe on both sides The relative angular displacement of the left lobe 1 of the gear and the right lobe 2 of the double-lobed gear eliminates the gear backlash when they mesh with other gears in the shaft system. When the eccentric shaft is designed, it should be ensured that the contact surface with the waist hole 7 is in a frictional self-locking state, so that the gear gap and preload can be precisely adjusted.

Let the radius of the left lobe 1 of the double-lobe gear be R, the distance from the center of the left rotating shaft to the center of the main shaft be r, the gear gap be Δt, the adjustment angle of the fine-tuning screw be α, and the eccentricity of the eccentric shaft be a. The relationship between them is as follows:

$\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arccos</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;t</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; r</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; a</span>}}<span\; class="notranslate">\; )</span>$

In this way, after the gear backlash Δt is measured, the angle at which the fine-tuning screw needs to be rotated can be calculated.

Claims (2)

1. A backlash elimination and micro-adjustment mechanism for a precision transmission system of a rotary table, characterized in that it includes: an eccentric shaft, a left lobe of a double-lobe gear, a right lobe of a double-lobe gear, a waist hole, a clamping screw, and a fine-tuning screw hole , dial, wherein: the waist hole is set on the left lobe of the double-lobe gear, the left half shaft of the eccentric shaft is sleeved in the waist hole, the right half shaft of the eccentric shaft is sleeved in the right lobe of the double-lobe gear, and the fine-tuning screw hole is set at the right end of the eccentric shaft , the clamping screw is screwed in from the left side of the double-lobe gear, the left lobe of the double-lobe gear and the right lobe of the double-lobe gear are connected together, and the dial is fixed on the right end of the right lobe of the double-lobe gear. 2. The backlash elimination and micro-adjustment mechanism of the precision transmission system of the rotary table according to claim 1, wherein the fine-tuning screw hole is a fine-tuning inner hexagonal screw hole.

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