Measuring head structure of ultra-precision optical measurement machine tool

Abstract

The invention discloses an ultra-precision optical measurement machine tool measuring head structure which is characterized by comprising an outer cylinder and an inner cylinder located in the outer cylinder, a floating rod is arranged in the inner cylinder, a probe is arranged on the floating rod, air floating structures are arranged on the outer cylinder and the inner cylinder, the floating rod can float in an inner hole of the inner cylinder through the air floating structures, and the probe is arranged on the probe. A reflecting mirror is installed on the floating rod, and a limiting structure for limiting rotation of the floating rod and a positioning structure for supporting the floating rod are arranged between the floating rod and the inner cylinder. A floating rod of the measuring head structure can float in an inner hole of an inner cylinder through an air floating structure so that interference of frictional resistance can be greatly avoided, a reflecting mirror is installed on the floating rod, and then the reflecting mirror is matched with a laser system and a receiver, so that tiny lifting changes of the floating rod can be detected by the laser system, and detection accuracy is improved. Therefore, precise measurement is realized.

Description

Technical Field

[0001] The invention relates to an ultra-precision optical measuring machine, in particular to an ultra-precision optical measuring machine tool probe structure. Background Art

[0002] In the ultra-precision machining production process, measurement is an important process. Whether the machined workpiece meets the requirements needs to be checked by measurement. However, for some workpieces with special shapes, the surface of the workpiece is a non-spherical free-form surface. If ordinary measuring equipment (such as micrometer measurement, etc.) is used for manual measurement, not only the measurement process is time-consuming but also the measurement accuracy is difficult to meet the requirements. Therefore, the applicant uses the current advanced laser system to design an ultra-precision optical measuring machine to measure the above structure. The ultra-precision optical measuring machine includes a laser system, a measuring seat and a probe. The workpiece to be measured is placed on the measuring seat. The probe in the probe contacts the surface of the workpiece, and the measuring seat drives the workpiece to move in a plane, and the probe can move up and down with the movement of the workpiece. The laser system emits laser to the reflector provided on the measuring seat and the probe and receives the reflected laser beam. The emitted laser beam changes with the movement of the measuring seat or the probe. Therefore, according to the change data of the reflected laser beam, the accurate size data of the workpiece surface can be known. In order to cooperate with the above measurement method, the present application designs a probe structure of an ultra-precision optical measuring machine tool, and the probe structure can accurately detect the height change of the object surface. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides an ultra-precision optical measuring machine tool probe structure.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] The ultra-precision optical measuring machine tool probe structure is characterized in that it includes an outer cylinder and an inner cylinder located in the outer cylinder, a floating rod is provided in the inner cylinder, a probe is provided on the floating rod, an air flotation structure is provided on the outer cylinder and the inner cylinder, the floating rod can float in the inner hole of the inner cylinder through the air flotation structure, a reflecting mirror is installed on the floating rod, and a limiting structure for limiting the rotation of the floating rod and a positioning structure for supporting the floating rod are provided between the floating rod and the inner cylinder.

[0006] The air flotation structure comprises an outer air inlet hole arranged on the outer cylinder, an annular air channel arranged on the inner cylinder and a plurality of inner air inlet holes arranged in the annular air channel, wherein the outer air inlet hole is communicated with the annular air channel, and the inner air inlet hole is communicated with the inner hole.

[0007] The inner air inlet hole is a tapered hole, and the hole diameter gradually decreases from the air inlet end hole of the inner air inlet hole to the air outlet end hole of the inner air inlet hole.

[0008] The positioning structure comprises a reference plate fixed on the floating rod and a reference ball arranged on the inner cylinder. Both ends of the reference plate can contact with the reference ball to support the floating rod.

[0009] The limiting structure includes limiting posts that are arranged opposite to each other, and the end of the reference plate is located between two corresponding limiting posts.

[0010] An end plate is provided at the end of the floating rod, a plate hole is provided between the end plate and the floating rod, and the reference plate passes through the plate hole and is fixed to the end plate.

[0011] A connecting screw hole is arranged in the floating rod, and a connecting thread matching with the connecting screw hole is arranged at the end of the probe.

[0012] It also includes a connecting flange, the bottom end of which is provided with two elastic rings and a clamp for locking the two elastic rings, the end of the outer tube is located in the two elastic rings and is fixed to the connecting flange by the elastic rings, the connecting flange includes a flange plate and a connecting tube, a transverse slit and a vertical incision are cut on the connecting tube, one end of the vertical incision is connected to the transverse slit, and the other end of the vertical incision is connected to the outside, and the elastic ring is formed by the division of the transverse slit and the vertical incision.

[0013] It also includes a probe lifting mechanism, which includes a lifting movable plate, a lifting air-floating guide rail and a lifting motor. The lifting motor is connected to the lifting air-floating guide rail, the lifting movable plate is installed on the lifting air-floating guide rail, and the connecting flange is connected to the lifting movable plate.

[0014] A lens adjustment mechanism is provided between the connecting flange and the lifting movable plate. The lens adjustment mechanism includes an adjustment spring, a plurality of adjustment screw holes provided on the connecting flange and an adjustment screw matched with the adjustment screw holes. One end of the adjustment spring abuts against the connecting flange and the other end abuts against the lifting movable plate.

[0015] The beneficial effects of the present invention are as follows: the present invention is a probe structure specially designed for precise measurement, the floating rod of the probe structure can float in the inner hole of the inner cylinder through the air flotation structure, thereby greatly avoiding the interference of friction resistance, and a reflector is installed on the floating rod, and then through the reflector and the laser system, it can be achieved that the slight lifting and lowering changes of the floating rod can be detected and calculated by the laser system, thereby achieving precise measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is the overall structural view of the present invention;

[0018] Figure 2 It is a cross-sectional structural view of the present invention;

[0019] Figure 3 It is the internal structure view of the present invention;

[0020] Figure 4 It is a structural view of the optical measuring machine tool;

[0021] Figure 5 This is a structural view of the flange plate and connecting tube. DETAILED DESCRIPTION

[0022] The advantages and features of the present disclosure and its implementation methods will be explained by the following embodiments described with reference to the accompanying drawings. However, the present disclosure can be embodied in different forms and should not be interpreted as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure will be comprehensive and complete, and will fully convey the scope of the present disclosure to those skilled in the art. In addition, the present disclosure is limited only by the scope of the claims.

[0023] The shapes, sizes, ratios, angles and numbers disclosed in the drawings for describing the embodiments of the present disclosure are only examples, and therefore the present disclosure is not limited to the details shown. Throughout this specification, the same reference numerals refer to the same elements. In the following description, when the detailed description of the relevant known functions or configurations is determined to be unnecessary to blur the focus of the present disclosure, the detailed description will be omitted. In the case of using "including", "having" and "comprising" described in this specification, other parts may be added unless "only" is used. Unless otherwise indicated, the terms in the singular may include plural forms.

[0024] When explaining an element, although not explicitly described, the element is understood to include a range of error.

[0025] When describing a positional relationship, for example, when the positional relationship is described as "on," "above," "below," and "adjacent to," unless "immediately" or "directly" is used, one or more parts may be arranged between two other parts.

[0026] When describing a time relationship, for example, when a time sequence is described as “after,” “subsequently,” “next,” and “before,” discontinuous cases may be included unless “just” or “directly” is used.

[0027] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from other elements. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the present disclosure.

[0028] As those skilled in the art can fully understand, the features of the different embodiments of the present disclosure can be coupled or combined with each other in part or in whole, and can cooperate with each other in various ways and be driven technically. The embodiments of the present disclosure can be performed independently of each other, or can be performed together in a mutually dependent relationship.

[0029] Reference Figures 1 to 5 The present invention discloses an ultra-precision optical measuring machine tool probe structure, comprising an outer cylinder 1 and an inner cylinder 2 located in the outer cylinder 1, the outer cylinder 1 and the inner cylinder 2 are both cylindrical cylinders, the outer cylinder 1 has a mounting hole, the inner cylinder 2 is located in the mounting hole, the outer cylinder 1 and the inner cylinder 2 can be fixed as a whole by pins, a floating rod 3 is provided in the inner cylinder 2, the floating rod 3 is a cylindrical rod, and is made of a lightweight magnesium alloy, so as to minimize the contact pressure during measurement, of course, a probe (not shown in the figure) is provided on the floating rod 3, the end face of the probe contacts the workpiece to be measured, when the measuring seat moves, the floating rod has a slight lifting change with the height change of the workpiece surface, a reflector 17 is installed on the floating rod 3, the reflector 17 is generally installed on the floating rod 3 by pasting, when the laser of the laser system irradiates the reflector 17, the reflector 17 will reflect the laser beam back Laser system, the laser system can calculate the precise size data of the workpiece surface through the reflected laser beam data. Of course, the laser system and the reflector 17 are purchased equipment, and they are not components of this structure. Therefore, their specific structure and principle are not described in detail. This probe structure adopts a combination of air flotation structure and laser detection for precise measurement. The floating rod of the probe structure can float in the inner hole of the inner cylinder through the air flotation structure, thereby greatly avoiding the interference of friction resistance. The outer cylinder 1 and the inner cylinder 2 are provided with an air flotation structure. The floating rod 3 can float in the inner hole of the inner cylinder 2 through the air flotation structure, and a limiting structure for limiting the rotation of the floating rod 3 and a positioning structure for supporting the floating rod 3 are provided between the floating rod 3 and the inner cylinder 2. Of course, in this application, the position of the floating rod 3 when it contacts the positioning structure is the reference position for measurement, which is convenient for subsequent calculations.

[0030] As shown in the figure, the air flotation structure includes an outer air inlet hole (not shown in the figure) arranged on the outer cylinder 1, an annular air channel 4 arranged on the inner cylinder 2, and a plurality of inner air inlet holes 5 arranged in the annular air channel 4. The inner air inlet holes 5 are evenly arranged around the inner hole of the inner cylinder 2. The outer air inlet hole is connected to the annular air channel 4, and the inner air inlet hole 5 is connected to the inner hole. The outer air inlet hole is connected to the external compressed air source through an air joint and an air pipe. The high-pressure gas enters the annular air channel 4 from the outer air inlet hole, and then enters the inner air inlet hole 5. In this way, a multi-point air intake structure can be formed in the inner hole of the inner cylinder 2, and the annular air channel 4 is provided with two upper and lower ones. Of course, the outer cylinder 1 is provided with an outer air channel connected to the annular air channel 4, and the outer air inlet hole is connected to the outer air channel, so that a relatively uniform high-pressure air film is formed in the inner hole, which helps to prevent eccentric micro-movement of the floating rod 3, thereby improving the measurement accuracy. As a further preferred structure, the inner air inlet hole 5 is a conical hole, and the aperture gradually decreases from the air inlet end hole to the air outlet end hole of the inner air inlet hole 5. By reducing the aperture, we can gradually increase the pressure of the gas entering the inner hole of the inner tube 2, thereby forming an air film with higher pressure, which helps to prevent eccentric micro-movement of the floating rod 3, thereby improving the measurement accuracy.

[0031] As shown in the figure, the positioning structure includes a reference plate 6 fixed on the floating rod 3 and a reference ball 7 arranged on the inner tube 2. The reference plate 6 is also a magnesium alloy plate and is relatively thin. The two ends of the reference plate 6 can contact with the reference ball 7 to support the floating rod 3. The reference ball 7 is a steel sphere. The position where the reference plate 6 contacts the steel sphere is the reference point position. The limiting structure includes relatively arranged limit columns 8. The end of the reference plate 6 is located between two corresponding limit columns 8. The limit columns 8 are made of ceramic and have a very smooth surface. The reference plate 6 can prevent the floating rod 3 from rotating and affecting the accuracy through the action of the limit columns 8, and the smooth surface of the ceramic can avoid affecting the lifting and lowering of the floating rod 3. Moreover, the limit columns 8 cooperate with the reference ball 7 to make the reference plate 6 contact with the reference ball 7 horizontally.

[0032] As shown in the figure, a connecting screw hole is provided in the floating rod 3, and a connecting thread matching the connecting screw hole is provided at the end of the probe, so that the probe is convenient to install and disassemble, and is convenient for later replacement. Furthermore, a weight-reducing hole 10 penetrating the connecting screw hole is provided on the floating rod 3. The floating rod 3 needs a lightweight design, which is beneficial to improving the measurement accuracy.

[0033] As a preferred structure, an end plate 9 is provided at the end of the floating rod 3, and a plate hole is provided between the end plate 9 and the floating rod 3. The reference plate 6 is fixed to the end plate 9 through the plate hole because the weight reduction hole 10 just passes through the plate hole, and the reference plate 6 is also fixed by bonding. In this way, the contact area between the reference plate 6 and the end face of the floating rod 3 is small, so the reference plate 6 and the end plate 9 are bonded as one. Of course, the end plate 9 is also a magnesium alloy and is bonded as one with the floating rod 3.

[0034] As shown in the figure, it also includes a connecting flange, and the outer cylinder 1 is connected to the probe lifting mechanism through the connecting flange. Two elastic rings 11 are provided at the bottom end of the connecting flange, and the end of the outer cylinder 1 is located in the two elastic rings 11 and is fixed to the connecting flange by the elastic rings 11, and the elastic ring 11 is locked by the clamp 12, and the clamp 12 is a purchased part. The above structure is simple and easy to assemble and disassemble, so that it is easy to realize the maintenance and replacement of the probe structure in the later stage. The specific structure of the connecting flange of the present application is: it includes a flange plate 14 and a connecting cylinder 15, and an annular transverse slit 16 and a vertical incision 13 are cut on the connecting cylinder 15. One end of the vertical incision 13 is connected to the transverse slit 16, and the other end of the vertical incision 13 is connected to the outside world. The elastic ring 11 is formed by the division of the transverse slit 16 and the vertical incision 13. The above structure is simple to process and has low cost.

[0035] As shown in the figure, as a further structure, it also includes a probe lifting mechanism, which is installed on the marble plate 18 on the frame. The probe lifting mechanism includes a lifting and moving plate 19, a lifting and floating guide rail and a lifting motor. The lifting motor is connected to the lifting and floating guide rail, and the lifting and moving plate 19 is installed on the lifting and floating guide rail. The connecting flange is connected to the lifting and moving plate 19. Through the above structure, we can realize that the inner cylinder 2 and the outer cylinder 1 can make compensatory corresponding movements with the movement of the floating rod 3. Because the pressure of the air film formed around the floating rod 3 in the inner cylinder 2 is not absolutely uniform, when the floating rod 3 moves and rises and falls during the measurement process, the pressure of the air film will change, which will affect the measurement accuracy. Therefore, in order to ensure that the pressure of the air film on the floating rod 3 during the measurement process is consistent, the probe lifting mechanism will follow the data changes of the probe in real time, and make compensatory corresponding movements with the movement of the probe, so that the position of the probe and the floating rod 3 relative to the inner cylinder 2 and the outer cylinder 1 remains unchanged, thereby ensuring that the measurement position remains unchanged, thereby ensuring that the contact pressure during measurement remains unchanged. Thereby improving the accuracy of measurement, the above-mentioned lifting motor can be a linear servo motor. Of course, the lifting motor and the lifting air-floating guide rail are existing technology products, so the specific structure and connection relationship are not described in detail.

[0036] As shown in the figure, a lens adjustment mechanism is provided between the connecting flange and the lifting and moving plate 19. The lens adjustment mechanism is used to adjust the angle of the reflector 17. The lens adjustment mechanism includes an adjustment spring (not shown in the figure), a plurality of adjustment screw holes provided on the connecting flange, and an adjustment screw 20 matched with the adjustment screw holes. In the present application, there are three adjustment screw holes and three adjustment screws 20 matched with the adjustment screw holes, which are evenly arranged around the inner cylinder 2. The adjustment screw 20 can be pressed against the lifting and moving plate 19 to control the relative angle between the connecting flange and the lifting and moving plate 19. After adjustment, the connecting flange and the lifting and moving plate 19 are locked by screws to maintain the angle. In order to facilitate adjustment, the connecting flange and the adjusting screw 20 are always kept in close contact. One end of the adjustment spring is against the connecting flange and the other end is against the lifting and moving plate 19, so that adjustment is more convenient and accurate.

[0037] The above is a detailed introduction to an ultra-precision optical measuring machine tool probe structure provided by an embodiment of the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technicians in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. An ultra-precision optical measuring machine tool probe structure, including the following features: An outer cylinder and an inner cylinder located in the outer cylinder, a floating rod is provided in the inner cylinder, a probe is provided on the floating rod, an air flotation structure is provided on the outer cylinder and the inner cylinder, the floating rod can float in the inner hole of the inner cylinder through the air flotation structure, a reflecting mirror is installed on the floating rod, and a limiting structure for limiting the rotation of the floating rod and a positioning structure for positioning the floating rod are provided between the floating rod and the inner cylinder.

2. The ultra-precision optical measuring machine tool probe structure according to claim 1, characterized in that: The air flotation structure comprises an outer air inlet hole arranged on the outer cylinder, an annular air channel arranged on the inner cylinder and a plurality of inner air inlet holes arranged in the annular air channel, wherein the outer air inlet hole is communicated with the annular air channel, and the inner air inlet hole is communicated with the inner hole.

3. The ultra-precision optical measuring machine tool probe structure according to claim 1, characterized in that: The inner air inlet hole is a tapered hole, and the hole diameter gradually decreases from the air inlet end hole of the inner air inlet hole to the air outlet end hole of the inner air inlet hole.

4. The ultra-precision optical measuring machine tool probe structure according to claim 1, characterized in that: The positioning structure comprises a reference plate fixed on the floating rod and a reference ball arranged on the inner cylinder. Both ends of the reference plate can contact with the reference ball to support the floating rod.

5. The ultra-precision optical measuring machine tool probe structure according to claim 4, characterized in that: The limiting structure includes limiting posts that are arranged opposite to each other, and the end of the reference plate is located between two corresponding limiting posts.

6. The ultra-precision optical measuring machine tool probe structure according to claim 4, characterized in that: An end plate is provided at the end of the floating rod, a plate hole is provided between the end plate and the floating rod, and the reference plate passes through the plate hole and is fixed to the end plate.

7. The ultra-precision optical measuring machine tool probe structure according to claim 4, characterized in that: A connecting screw hole is arranged in the floating rod, and a connecting thread matching with the connecting screw hole is arranged at the end of the probe.

8. The ultra-precision optical measuring machine tool probe structure according to claim 1, characterized in that: It also includes a connecting flange, the bottom end of which is provided with two elastic rings and a clamp for locking the two elastic rings, the end of the outer tube is located in the two elastic rings and is fixed to the connecting flange by the elastic rings, the connecting flange includes a flange plate and a connecting tube, a transverse slit and a vertical incision are cut on the connecting tube, one end of the vertical incision is connected to the transverse slit, and the other end of the vertical incision is connected to the outside, and the elastic ring is formed by the division of the transverse slit and the vertical incision.

9. The ultra-precision optical measuring machine tool probe structure according to claim 8, characterized in that: It also includes a probe lifting mechanism, which includes a lifting movable plate, a lifting air-floating guide rail and a lifting motor. The lifting motor is connected to the lifting air-floating guide rail, the lifting movable plate is installed on the lifting air-floating guide rail, and the connecting flange is connected to the lifting movable plate.

10. The ultra-precision optical measuring machine tool probe structure according to claim 8, characterized in that: A lens adjustment mechanism is provided between the connecting flange and the lifting movable plate, and the lens adjustment mechanism includes an adjustment spring, a plurality of adjustment screw holes provided on the connecting flange, and an adjustment screw matched with the adjustment screw holes. One end of the adjustment spring abuts against the connecting flange and the other end abuts against the lifting movable plate.

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