Hollow shaft taper squeeze encoder

Abstract

The hollow shaft taper extrusion type encoder relates to the technical field of encoders. The encoder includes: a tapered screw, an extrusion assembly, a housing assembly, a PCB assembly, a grating assembly, a main shaft, a main body, a bearing assembly and a light source; the extrusion assembly, the housing assembly, the PCB assembly, the grating assembly, the main shaft and the main body are coaxially arranged; the main shaft is provided with a limit edge, the main shaft passes through the main body, and the main shaft and the main body are assembled together by the limit edge and the bearing assembly sleeved outside the main shaft; the light source is installed inside the main body; the grating assembly is installed above the main shaft and is clamped to the main body by the PCB assembly arranged above the grating assembly; the housing assembly is arranged at the outermost side, and the housing assembly and the main body are assembled together by a tapered screw passing through the extrusion assembly and the main shaft, and the installation direction of the tapered screw is parallel to the axial direction. The present invention adopts a multi-faceted contact extrusion method to ensure that the customer's shaft end face is not damaged during installation. After installation, it can also meet the actual clamping requirements and will not cause the clamping shaft wall to break.

Description

Technical Field

[0001] The invention relates to the technical field of encoders, and in particular to a hollow shaft taper extrusion type encoder. Background Art

[0002] With the development of science and technology and the needs of economic development, encoders have been widely used in industries such as machine tools, elevators, servo motor accessories, textile machinery, packaging machinery, printing machinery, and lifting machinery. Encoders are devices that compile and convert signals (such as bit streams) or data into signal forms that can be used for communication, transmission, and storage. As the requirements for angle measurement accuracy increase, the requirements for the number of bits output by the encoder also increase. However, the increase in output bits also brings the problem of increased size. In many cases, the main instrument requires the encoder to be as small as possible. This requires that measures be taken in the design of the encoder to simplify the structure as much as possible, reduce the encoder size, and enhance market competitiveness. Currently, various fields such as domestic robotics require encoders with thin thickness, high installation requirements, and high precision. However, the domestic encoder industry cannot reduce the height of the encoder due to the use of traditional fixing methods.

[0003] 1. Disadvantages of traditional encoder top screw shaft

[0004] 1.1. The common screw sizes for screw-type encoders range from M4*4mm to M4*6mm, requiring the fixed shaft end to be at least 7mm thick. If this mounting method is used, the encoder will still require an additional 7mm of fixed shaft end thickness, even if the internal design height is reduced. This cannot meet the market demand for ultra-thin products. (Total encoder height = internal design height + fixed shaft end thickness.)

[0005] 1.2. The encoder base shaft tolerance is usually G7 / h6. If the client shaft diameter is In this installation method, the encoder shaft hole tolerance is G7 (tolerance range: +0.028mm to +0.007mm), and the client shaft diameter tolerance is h6 (tolerance range: +0mm to -0.013mm). With this installation method, the better the fit between the shaft and hole, the better the concentricity; conversely, the worse the fit, the worse the concentricity. If the client shaft is machined too small, installation concentricity will be poor, resulting in reduced encoder life and loss of encoder accuracy.

[0006] 1.3. The jackscrew-type shaft clamping method uses jackscrews to secure two points at 90 degrees, one end against the flattened portion of the client shaft and the other against the rounded portion. Due to the small contact surface at the front end of the jackscrew, anaerobic adhesive can cause the jackscrews to loosen after prolonged standby vibration and aging. This can cause the encoder's initial installation angle to shift, increasing the device's error and, in severe cases, causing equipment failure.

[0007] 2. Disadvantages of traditional encoder clamping method

[0008] 2.1. The commonly used hexagon socket screws for clamping encoders are M3 to M4, with a head diameter of This means the clamping shaft end thickness must be within the range of M3 = 8mm and M4 = 9mm. If the encoder is designed with this mounting method, the internal design height will increase by at least 8mm, making the clamping shaft end thickness unsuitable for ultra-thin products. (Total encoder height = internal design height + fixed shaft end thickness.)

[0009] 2.2. The encoder base shaft tolerance is usually G7 / h6. If the client shaft diameter is In this case, the encoder shaft hole tolerance is G7 (tolerance range: +0.028mm to +0.007mm), and the client shaft diameter tolerance is h6 (tolerance range: +0mm to -0.013mm). This installation method uses a 0.5mm thick clamping shaft made of 304 steel. The best clamping effect is achieved when the shaft and hole are well matched. If the client shaft diameter is too small during machining, insufficient clamping may occur during installation, resulting in shaft wall fracture and encoder installation failure or even scrapping. Summary of the Invention

[0010] To address the problems existing in the prior art, the present invention provides a hollow-shaft tapered squeeze encoder. This encoder addresses height issues associated with traditional screw-type and clamping installation methods, as well as issues with poor concentricity due to poor shaft machining tolerances, loosening due to aging, and shaft wall fracture. It also addresses issues with screw installation force and shaft end damage associated with eccentric screw-shaft squeeze installation.

[0011] The technical solutions adopted by the present invention to solve the technical problems are as follows:

[0012] A hollow shaft taper extrusion encoder, the encoder comprising: a tapered screw, an extrusion assembly, a housing assembly, a PCB assembly, a grating assembly, a spindle, a main body, a bearing assembly and a light source; the extrusion assembly, housing assembly, PCB assembly, grating assembly, main shaft and main body are coaxially arranged; the main shaft is provided with a limiting edge, the main shaft passes through the main body, is limited by the limiting edge and the main shaft and the main body are assembled together by a bearing assembly sleeved outside the main shaft; the light source is installed inside the main body; the grating assembly is installed above the main shaft and is clamped to the main body by a PCB assembly arranged above the grating assembly; the housing assembly is arranged at the outermost side, and the housing assembly and the main body are assembled together by a tapered screw passing through the extrusion assembly and the main shaft, and the installation direction of the tapered screw is parallel to the axial direction.

[0013] Preferably, the upper surface of the encoder is a plane.

[0014] Preferably, the bevel portion of the conical screw is 5°.

[0015] Preferably, the inclination angle of the inner hole of the extrusion assembly is 5°.

[0016] Preferably, the adjustable range of the conical screw and the main shaft is within 0.2 mm.

[0017] Preferably, the conical screw is made of 304 stainless steel / 06Cr19Ni10.

[0018] Preferably, the extrusion assembly is made of polytetrafluoroethylene and LV12 / 2A12 aluminum.

[0019] Preferably, the aperture of the extrusion assembly is less than or equal to When using polytetrafluoroethylene, the pore size is larger than LV12 / 2A12 aluminum is used.

[0020] Preferably, internal threads are provided in the apertures of the extrusion assembly and the main shaft.

[0021] Preferably, the bearing assembly is a double bearing.

[0022] The beneficial effects of the present invention are as follows: the hollow shaft taper extrusion encoder is installed using a taper screw and an extrusion assembly, ensuring that all shafts with a processing error of less than 0.2mm can be installed, reducing the problem of shaft processing accuracy. The taper screw is made of 304 stainless steel / 06Cr19Ni10 to ensure that it will not rust when used in humid environments and salt spray environments. The extrusion assembly is made of polytetrafluoroethylene and LV12 / 2A12 aluminum. Polytetrafluoroethylene has excellent chemical stability, corrosion resistance, and heat resistance. LV12 aluminum has high strength and a certain degree of heat resistance. The taper extrusion installation method adopts internal extrusion installation. The encoder height reaches about 18mm, which can realize the ultra-thin products required by the market. The taper extrusion installation method adopts a multi-faceted contact extrusion method to ensure that the end face of the customer shaft is not damaged during installation. In view of the low tolerance requirements of the customer shaft, the actual clamping requirements can be met after installation, and the clamping shaft wall will not break. It can be applied to encoders of various apertures. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Exploded view of the hollow shaft taper extrusion encoder of the present invention.

[0024] Figure 2 Assembly diagram of the hollow shaft taper extrusion encoder of the present invention.

[0025] Figure 3 A top view of the hollow shaft taper extrusion encoder of the present invention.

[0026] Figure 4A partial enlarged view of the hollow shaft taper extrusion encoder of the present invention.

[0027] Figure: 1. Conical screw, 2. Extrusion assembly, 3. Housing assembly, 4. PCB assembly, 5. Grating assembly, 6. Spindle, 7. First bearing, 8. Main body, 9. Second bearing, 10. Light source DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0029] like Figure 1 and Figure 2 As shown, a hollow shaft taper extrusion type encoder includes: a tapered screw 1, an extrusion component 2, a housing component 3, a PCB component 4, a grating component 5, a main shaft 6, a main body 8, a bearing component and a light source 10; the extrusion component 2, the housing component 3, the PCB component 4, the grating component 5, the main shaft 6 and the main body 8 are coaxially arranged; the bearing component includes a first bearing 7 and a second bearing 8. The spindle 6 is provided with a stopper edge and passes through the main body 8. The stopper edge fixes the main body 8 and the spindle 6 relative to each other, and the spindle 6 and the main body 8 are assembled together by a first bearing 7 and a second bearing 8 sleeved outside the spindle. A light source 10 is mounted inside the main body 8, corresponding to the grating assembly 5 and the PCB assembly 4. The grating assembly 5 is mounted above the spindle 6 and is clamped to the main body 8 by the PCB assembly 4 disposed above the grating assembly 5. The housing assembly 3 is disposed on the outermost portion and is threadedly connected to the extrusion assembly 2 and the spindle 6 by a tapered screw 1, thereby assembling the housing assembly 3 and the main body 1 together. The installation direction of the tapered screw 1 is parallel to the axial direction. This installation method differs from the structures of existing screw-type encoders and locking-type encoders. For assembly purposes, the spindle of both existing encoders has a boss in the assembly, while the encoder of the present invention has a flat top surface, significantly reducing the overall height of the product.

[0030] The beveled portion of the conical screw 1 is 5°, and the threaded portion of the inner hole of the extrusion component 2 threadedly connected to the conical screw 1 is also inclined at 5°. The inner hole of the main shaft 6 also has an internal thread, and the adjustable range of the conical screw 1 and the main shaft 6 is within 0.2mm. The conical screw 1 is made of 304 stainless steel / 06Cr19Ni10, with a tensile strength of: σb (MPa) ≥ 515-1035, and a hardness of: ≤ 201HBW; ≤ 92HRB; ≤ 210HV. The extrusion component 2 can be made of polytetrafluoroethylene and LV12 / 2A12 aluminum. Which material to use is selected based on the size of the aperture on the extrusion component 2: when the aperture of the extrusion component 2 is less than or equal to When using polytetrafluoroethylene, polytetrafluoroethylene has a high temperature range of 200 to 260 degrees and a low temperature range of -100 degrees without deformation. LV12 / 2A12 aluminum is used. LV12 / 2A12 aluminum can withstand high temperatures of 150 degrees and low temperatures of -60 degrees without deformation.

[0031] The above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or perform equivalent replacements on some of the technical features thereof. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. Hollow shaft taper extrusion encoder, characterized in that, The encoder includes: a tapered screw, an extrusion assembly, a shell assembly, a PCB assembly, a grating assembly, a main shaft, a main body, a bearing assembly and a light source; the extrusion assembly, the shell assembly, the PCB assembly, the grating assembly, the main shaft and the main body are coaxially arranged; the main shaft is provided with a limiting edge, the main shaft passes through the main body, is limited by the limiting edge and the main shaft and the main body are assembled together by a bearing assembly sleeved outside the main shaft; the light source is installed inside the main body; the grating assembly is installed above the main shaft and is clamped to the main body by a PCB assembly arranged above the grating assembly; the shell assembly is arranged at the outermost side, and the shell assembly and the main body are assembled together by a tapered screw passing through the extrusion assembly and threaded connection with the main shaft, the installation direction of the tapered screw is parallel to the axial direction, the hollow shaft taper extrusion encoder is installed using the tapered screw and the extrusion assembly, the bevel part of the tapered screw is 5°, and the inclination angle of the inner hole of the extrusion assembly is 5°.

2. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The upper surface of the encoder is a plane.

3. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The adjustable range of the conical screw and the main shaft is within 0.2 mm.

4. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The conical screw is made of 304 stainless steel / 06Cr19Ni10.

5. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The extruded components are made of polytetrafluoroethylene and LV12 / 2A12 aluminum.

6. The hollow shaft taper extrusion encoder according to claim 5, characterized in that: When the hole diameter on the extrusion component is less than or equal to φ30mm, polytetrafluoroethylene is used, and when the hole diameter is greater than φ30mm, LV12 / 2A12 aluminum is used.

7. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The extrusion assembly and the main shaft are provided with internal threads in the aperture.

8. The hollow shaft taper extrusion encoder according to claim 1, characterized in that: The bearing assembly is a double bearing.

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