Feedback element mounting structure and ultra-precision hydrostatic guideway applying same

A feedback element mounting structure and the technical field of ultra-precision hydrostatic guide rails using it

[0001] The present invention relates to the technical field of ultra-precision hydrostatic guide rails, and more specifically to a feedback element mounting structure and an ultra-precision hydrostatic guide rail using it.

Background technique

[0002] The presence of a high resolution feedback element currently sold on the market applicability of nanometer resolution in the feed, practical application is difficult in commercialization of ultra-precision machine tool real current feeding capacity corresponding to the resolution, and Due to environmental temperature fluctuations, the linear axis of ultra-precision machine tools may have thermal drift and thermal stress feedback components. In order to eliminate the thermal stress function of contact-mounted feedback system components (grating scales, holographic linear gratings, etc.), and to reduce the influence of ambient temperature fluctuations and airflow on the feedback system components through a semi-enclosed structure, the high-resolution feedback components are improved In terms of applicability and robustness in nanometer-level resolution feed, we propose a mounting structure for feedback components of ultra-precision hydrostatic guides.

[0003] Therefore, how to provide a feedback element mounting structure and an ultra-precision hydrostatic guide rail using it is an urgent problem to be solved by those skilled in the art.

Summary of the invention

[0004] In view of this, the present invention provides a feedback element mounting structure and an ultra-precision hydrostatic guide rail using it, so as to at least solve one of the problems raised in the background art section.

[0005] In order to achieve the above solution, the present invention adopts the following technical solutions:

[0006] A feedback element mounting structure, including a connecting plate, a grating mounting plate, a grating and a reading head, a reading head bracket and a reading head bent plate; the grating mounting plate includes a fixed connection part and two An elastically deformable connecting portion, the connecting portion of the elastically deformable connecting portion and the fixed connecting portion is provided with a gap, and the elastically deformable connecting portion is also provided with an n-shaped elastic deformation seam; the middle part of the connecting plate is connected with The fixed connecting portion of the grating mounting plate is connected, and the two ends of the connecting plate are respectively connected to the two elastically deformable connecting portions through connecting pieces; the middle of the grating is fixed on the grating mounting plate, and both ends are pressed The tightening piece is tightly installed on the grating mounting plate; the reading head is installed on the reading head bent plate through the reading head bracket.

[0007] Preferably, in the above-mentioned feedback element installation structure, the horizontal direction and rotation angle of the reading head bracket on the reading head bend plate are fine-tuned to adjust the gap between the grating and the reading head.

[0008] Preferably, in the above-mentioned feedback element mounting structure, the middle of the grating is fixed to the fixed connection part of the grating mounting plate by bonding, and both ends are pressed on the grating mounting plate with elastic pressing plates.

[0009] Preferably, in the above-mentioned feedback element mounting structure, it further includes a grating cover, which covers the connecting plate, grating mounting plate, grating and reading head, reading head bracket and reading head bent plate. Within.

[0010] Preferably, in the above-mentioned feedback element installation structure, a positive pressure gas inlet is opened on the grating outer cover, and an air inlet quick connector is installed on the positive pressure gas inlet.

[0011] An ultra-precision hydrostatic guide rail using a feedback element mounting structure, including a feedback element mounting structure, a guide rail, an air inlet quick-connect connector, a linear motor, a slide and a grating cover, and the slide is slidably mounted on the On the guide rail and driven by the linear motor; the connecting plate of the feedback element mounting structure is fixedly connected to the slide plate through the connecting piece, and the reverse

The reading head bent plate of the feeding element mounting structure is connected to the side of the guide rail; the grating housing covers the connecting plate, the grating mounting plate, the grating and the reading head, the reading head bracket and the reading head bent plate, and the The air inlet quick-plug connector is installed on the positive pressure gas inlet opened in the grating outer cover.

[0012] It can be seen from the above technical solutions that, compared with the prior art, the present disclosure provides a feedback element mounting structure and an ultra-precision hydrostatic guide rail using it. The present invention is comparable to the existing ultra-precision hydrostatic The installation structure of the feedback element of the guide rail is different. The existing structure is to directly bond the middle of the grating to the grating mounting plate or slide plate, or directly bond the middle of the grating to the guide rail, and fix the grating ruler only by pressing both ends. Relying on the low thermal expansion coefficient material of the grating itself and the compression method at both ends to release the thermal stress of the grating system, it is not possible to eliminate the influence of thermal deformation on the grating mounting base surface, and it is also difficult to reduce the drift of the grating as a whole with the structural parts.

[0013] The present invention solves the thermal stress problem of the feedback element in the high-resolution feed of the large-stroke moving part, and makes the feedback element of the ultra-precision hydrostatic guideway less susceptible to environmental temperature fluctuations and airflow to the feedback system through the semi-closed structure Due to the influence of the components, there is positive air pressure in the semi-closed structure, and the feedback components are prevented from polluting the feedback components by factors such as dust and oil mist in the environment through the gap seal.

Description of the drawings

[0014] In order to more clearly explain the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, in the following description The drawings are merely embodiments of the present invention. For those of ordinary skill in the art, other drawings may be obtained based on the provided drawings without creative work.

[0015] FIG. 1 is an overall schematic diagram of an ultra-precision hydrostatic guide rail using a feedback element mounting structure;

[0016] FIG. 2 is a schematic diagram of the elastic connection of the feedback element mounting structure;

[0017] FIG. 3 is a schematic diagram of the installation relationship between the connecting plate, the grating mounting plate, the grating and the reading head;

[0018] FIG. 4 is a schematic diagram of the structure of the grating mounting plate.

Detailed ways

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0020] The embodiment of the present invention discloses a feedback element mounting structure, including a connecting plate 1, a grating mounting plate 2, a grating 3 and a reading head 4, a reading head bracket 5 and a reading head bent plate 6; the grating mounting plate 2 includes a fixed The connecting portion 7 and the elastically deformable connecting portion 8 at both ends of the fixed connecting portion 7 are provided with a gap 9 at the connection between the elastically deformable connecting portion 8 and the fixed connecting portion 7, and the elastically deformable connecting portion 8 is also provided with an n-shaped elastic deformation seam 10; The middle part of the connecting plate 1 is connected to the fixed connecting portion 7 of the grating mounting plate 2 through a connecting piece, and the two ends of the connecting plate 1 are respectively connected to two elastically deformable connecting portions 8 through connecting pieces; the grating 3 is fixed to the grating mounting plate 2 in the middle The two ends are compressed and installed on the grating mounting plate 2 by pressing parts; the reading head 4 is installed on the reading head bent plate 6 through the reading head bracket 5.

[0021] The selection of the low thermal expansion coefficient of the grating mounting plate 2 will only produce a small thermal stress with the grating 3 when the ambient temperature fluctuates, and there will be no thermal drift between the two due to the intermediate bonding; The connection between the grating mounting plate 2 and the connecting plate 1 of the same material as the sliding plate 15 is fixed in the middle, and the two ends are elastic hinge structures to avoid slippage.

The thermal deformation of the board 15 and the connecting board 1 directly affects the grating mounting board 2. The thermal stability of the system movement and the avoidance of the thermal stress of the system can realize large-stroke nano-resolution movement feed and be applied to ultra-precision processing machine tools.

[0022] In order to further optimize the above technical solution, by fine-tuning the horizontal direction and rotation angle of the reading head bracket 5 on the reading head bent plate 6, and then adjusting the gap between the grating 3 and the reading head 4.

[0023] In order to further optimize the above technical solution, the middle of the grating 3 is fixed to the fixed connecting portion 7 of the grating mounting plate 2 by bonding, and both ends are pressed on the grating mounting plate 2 with elastic pressing plates.

[0024] In order to further optimize the above technical solution, it also includes a grating cover 11, which covers the connecting plate 1, the grating mounting plate 2, the grating 3 and the reading head 4, the reading head bracket 5 and the reading head bending plate 6 .

[0025] In order to further optimize the above technical solution, the grating housing 11 is provided with a positive pressure gas inlet, and the positive pressure gas inlet is equipped with an air inlet quick connector 12, and the air inlet quick connector 12 is provided for the grating housing 11 Clean and dry compressed air. The grating cover 11 is designed to prevent air from directly blowing the connecting plate 1, grating mounting plate 2, grating 3, reading head 4, reading head bracket 5 and other key components through the pipeline design, and pass through the system cavity. Pressure and gap seal to avoid the environment dust, oil mist and other factors polluting the feedback element.

[0026] An ultra-precision hydrostatic guide rail using a feedback element installation structure, including a feedback element installation structure, a guide rail 13, an air inlet quick connector 12, a linear motor 14, a slide 15 and a grating cover 11, and the slide 15 slides Installed on the guide rail 13 and driven by the linear motor 14; the connecting plate 1 of the feedback element installation structure is fixedly connected with the slide plate 15 through the connecting piece, the reading head bent plate 6 of the feedback element installation structure is connected with the side of the guide rail 13; the grating cover 11 Cover the connecting plate 1, the grating mounting plate 2, the grating 3 and the reading head 4, the reading head bracket 5 and the reading head bend plate 6, and install the air inlet quick connector 12 on the positive pressure gas inlet of the grating cover 11 superior.

[0027] The guide rail 13 is assembled from high-strength casting materials and then scraped as a whole, which is the basis for the accuracy of the moving parts. The slide 15 is a moving part, which is supported by a static pressure slider to move on the guide rail 13. The drive of the carriage 15 is realized by the use of a linear motor 14 in conjunction with a high-resolution closed-loop feedback system, wherein the high-resolution closed-loop feedback system mainly adopts the grating 3 system.

[0028] The movement of the carriage 15 is controlled by a set of nanometer-resolution numerical control system. The numerical control system sends movement instructions to control the movement of the linear motor 14. The reading head 4 and the grating 3 produce relative movement, and the reading head 4 detects the corresponding Position signal, and feedback the signal to the CNC system. The core point of the device of the present invention is that the grating mounting plate 2 is not directly connected to the slide plate 15. The grating mounting plate 2 is designed with an elastic hinge structure, and a low thermal expansion coefficient is selected. The method is to allow elastic deformation at both ends of the fixed middle. When the sliding plate 15 and the connecting plate 1 are thermally deformed due to the heat of the environment or the hydrostatic bearing medium, they are fixed in the middle to avoid the thermal drift of the grating 3 relative to the reading head 4, and the connection is eliminated by the elastic structure of the grating mounting plate 2. Thermal stress caused by board 1.

[0029] The various embodiments in this disclosure are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0030] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this document, but should conform to the widest scope consistent with the principles and novel features disclosed in this document.