Digital display length measuring instrument

Abstract

The invention discloses a digital display length measuring instrument, and belongs to the technical field of metering devices. The device comprises a U-shaped main scale frame, one end of the U-shaped main scale frame is provided with a universal spiral measuring mechanism, the other end of the U-shaped main scale frame is provided with a digital display spiral measuring mechanism, and the digital display spiral measuring mechanism comprises a fixed screw sleeve, a micro-motion measuring anvil, a rotating gear sleeve, a planet carrier, a fixed wheel, a differential turntable and a digital display module. One end of the fixed screw sleeve is fixedly connected with a right arm end sleeve of the U-shaped main scale frame, the other end of the fixed screw sleeve is in threaded connection with the rotating gear sleeve, one end of the planet carrier is rotatably connected with the rotating gear sleeve through the coaxial planet wheel set, and the other end of the planet carrier is rotatably arranged in the fixed wheel and inserted into the differential rotating disc to be coaxially and rotatably connected with the outer end of the fixed wheel. Differential scale marks are arranged on the large outer cylindrical surface of the differential turntable, and a digital display module is arranged on the fixed screw sleeve; according to the invention, an epicyclic gear train with a high reduction ratio is combined with a spiral structure, so that high-precision axial displacement control is realized.

Description

Technical Field

[0001] The invention relates to a digital display length measuring instrument, belonging to the technical field of measuring devices. Background Art

[0002] In industrial manufacturing enterprises, vernier calipers are commonly used to measure length, and the accuracy is generally accurate to 0.02 mm. If the requirements are higher, micrometers are also used. Due to the limitations of the thread structure (geometric dimensions, strength, rigidity, etc.), the pitch of the micrometer is 0.5mm, and the periphery of the movable sleeve is divided into 50 equal parts. The reading corresponding to each grid is 0.01mm, and the reading is estimated to be one decimal place. The measurement accuracy is difficult to improve.

[0003] The development of modern industrial technology has put forward higher and higher requirements for the machining accuracy of parts. When the enterprise debugs the equipment for bearing finishing production, if the outer diameter micrometer is used for measurement, the detection effect is not ideal, because the outer ring accuracy of the bearing itself is at the micron level. It is best to use a higher-level measuring instrument to obtain more accurate measurement data and control the outer diameter size within a more reasonable size range. Especially when measuring parts at critical sizes, it is difficult to accurately judge whether they are qualified without using a higher-level measuring instrument, and it is easy to misjudge. Therefore, it is very necessary to design an ultra-high-level length measuring instrument. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a digital length measuring instrument to achieve high-precision axial displacement control; In order to achieve the above purpose / solve the above technical problems, the present invention is implemented by adopting the following technical solutions: A digital length measuring instrument comprises a U-shaped main scale frame, one end of the U-shaped main scale frame is provided with a universal spiral measuring mechanism, and the other end is provided with a digital spiral measuring mechanism; Wherein, the digital display spiral measuring mechanism comprises a fixed screw sleeve, a micro-motion measuring anvil, a rotating gear sleeve, a planetary carrier, a fixed wheel, a differential turntable and a digital display module, one end of the fixed screw sleeve is fixedly connected to the sleeve at the right arm end of the U-shaped main scale frame, and the other end is threadedly connected to the rotating gear sleeve, one end of the planetary carrier is rotatably connected to the rotating gear sleeve through a coaxial planetary gear set, and the other end is rotatably arranged in the fixed wheel and inserted into the differential turntable and coaxially rotatably connected with the outer end of the fixed wheel, a differential scale line is arranged on the large outer cylindrical surface of the differential turntable, and a digital display module is arranged on the fixed screw sleeve; The micro-motion measuring anvil slides through the fixed screw sleeve and extends into the groove of the U-shaped main scale frame.

[0005] Optionally, a manual knob is provided at the outer end of the differential dial, and a second force measuring device is also provided at the outer end of the manual knob.

[0006] Optionally, a fixing sleeve connected to the right arm end is provided at one end of the fixing screw sleeve, and an internal thread matching the external thread of the rotating gear sleeve is provided inside the fixing screw sleeve.

[0007] Optionally, an internal gear is provided in the rotating gear sleeve, and a planetary gear 1 meshing with the internal gear is provided at one end of the coaxial planetary gear set, and a planetary gear 2 meshing with the internal gear of the fixed wheel is provided at the other end.

[0008] Optionally, the number of teeth of the internal gear in the rotating gear sleeve is one more than the number of teeth of the internal gear in the fixed wheel.

[0009] Optionally, the number of teeth of the planetary gear one is equal to that of the planetary gear two.

[0010] Optionally, the planetary carrier includes a coaxial inner guide column, a guide ring, an outer guide column and a connecting column, the inner guide column is rotatably arranged in a rotating gear sleeve, the outer guide column is rotatably arranged in a fixed wheel, the outer end surface of the guide ring is slidingly matched with the inner end surface of the fixed wheel, and the connecting column is inserted into the inner hole of the differential turntable and fixedly connected to the differential turntable by a radial tightening screw.

[0011] Optionally, a second locking mechanism is provided on the sleeve-shaped right arm end of the U-shaped main scale frame for locking the micro-motion anvil.

[0012] Optionally, a locking mechanism 1 is provided on the sleeve-shaped left arm end of the U-shaped main scale frame for locking the universal spiral measuring mechanism.

[0013] Optionally, both sides of the U-shaped main scale frame are wrapped with insulation sheets to isolate human body temperature during measurement.

[0014] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the measuring instrument of the present invention can be used as an ordinary micrometer or as a length measuring instrument with higher precision; in the spiral measuring mechanism of the present invention, a fixed wheel, a planetary carrier, a rotating gear sleeve, and a coaxial planetary gear set are used to form an epicyclic gear train, the rotating gear sleeve has one more tooth than the fixed wheel, and the rotating gear sleeve rotates one tooth in the same direction for every clockwise rotation of the differential turntable, and a high reduction ratio epicyclic gear train is combined with a spiral structure to achieve high-precision axial displacement control. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Shown is a front view of the digital length measuring instrument of the present invention; Figure 2 Shown is an exploded view of the digital length measuring instrument of the present invention; Figure 3 The figure shows a partial cross-sectional view of the digital length measuring instrument of the present invention; Figure 4 The figure shows a rear view of the digital length measuring instrument of the present invention; In the figure: U-shaped main scale frame 01, left arm end 011, right arm end 012, insulation sheet 013; Universal spiral measuring mechanism: Micrometer screw 11, fixed sleeve 12, differential cylinder 13, force measuring device 14, locking mechanism 15; Digital spiral measuring mechanism: Fixed screw sleeve 21, fixed sleeve 211, internal thread 212, micro-motion anvil 22, rotating gear sleeve 23, planetary carrier 24, inner guide column 241, guide ring 242, outer guide column 243, connecting column 244, coaxial planetary gear set 25, planetary gear one 251, planetary gear two 252, fixed wheel 26, differential turntable 27, screw 28, force measuring device two 29, locking mechanism two 30, digital display module 31. DETAILED DESCRIPTION

[0016] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0017] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0019] like Figure 1-Figure 4As shown, a digital display length measuring instrument comprises a U-shaped main scale frame 01, wherein one end of the U-shaped main scale frame 01 is provided with a universal spiral measuring mechanism, and the other end is provided with a digital display spiral measuring mechanism; Among them, the digital display spiral measuring mechanism includes a fixed screw sleeve 21, a micro-motion anvil 22, a rotating gear sleeve 23, a planetary carrier 24, a coaxial planetary gear set 25, a fixed wheel 26, a differential turntable 27 and a digital display module 31. One end of the fixed screw sleeve 21 is fixedly connected to the sleeve at the right arm end 012 of the U-shaped main scale frame 01, and the other end is threadedly connected to the rotating gear sleeve 23. One end of the planetary carrier 24 is rotatably connected to the rotating gear sleeve 23 through the coaxial planetary gear set 25, and the other end is rotatably arranged in the fixed wheel 26 and inserted into the differential turntable 27 and coaxially rotatably connected to the outer end of the fixed wheel 26. Differential scale lines are provided on the large outer cylindrical surface of the differential turntable 27, and a digital display module 31 is provided on the fixed screw sleeve 21 for easy reading.

[0020] The micro-motion measuring anvil 22 slides through the fixed screw sleeve 21 and extends into the groove of the U-shaped main scale frame 01; One end of the fixed screw sleeve 21 is provided with a fixed sleeve 211 connected to the right arm end 012, and the fixed screw sleeve 21 is provided with an internal thread 212 matching the external thread of the rotating gear sleeve 23, and the pitch of the precision internal thread is 0.5 mm.

[0021] The rotating gear sleeve 23 is provided with an internal gear, and the coaxial planetary gear set 25 is provided with a planetary gear 1 251 meshing with the internal gear at one end, and a planetary gear 252 meshing with the internal gear of the fixed wheel 26 at the other end.

[0022] Principle of spiral measuring mechanism: In the high-precision spiral measuring mechanism, the fixed wheel 26, the planet carrier 24, the rotating gear sleeve 23, the coaxial planetary gear set 25, etc. constitute an epicyclic gear train. The number of teeth of the planetary wheel 1 251 and the planetary wheel 2 252 is equal. The rotating gear sleeve 23 has one more tooth than the fixed wheel 26. Every time the differential turntable 27 rotates clockwise for one circle, the rotating gear sleeve 23 rotates one tooth in the same direction. In the example, the differential turntable 27 rotates clockwise for 40 circles, the rotating gear sleeve 23 rotates one circle in the same direction, and the micro-motion measuring anvil 22 moves axially by one tooth pitch of 0.5 mm. One rotation of the differential turntable 27 corresponds to an axial movement of the micro-motion anvil 22 of 0.5 mm / 40=0.0125 mm; each rotation of the differential turntable 27 by one scale corresponds to an axial movement of the micro-motion anvil 22 of 0.0125 mm / 100=0.000125 mm. In the specific implementation of this embodiment, the number of teeth of the internal gear in the rotating gear sleeve 23 is one more than the number of teeth of the internal gear in the fixed wheel 26. In this example, the number of teeth of the internal gear in the fixed wheel 26 is 40, and the number of teeth of the internal gear in the rotating gear sleeve 23 is 41. The number of teeth of the planetary gear 1 251 is equal to that of the planetary gear 2 252. In the specific implementation of this embodiment, the planet carrier 24 includes a coaxial inner guide column 241, a guide ring 242, an outer guide column 243 and a connecting column 244. The inner guide column 241 is rotatably disposed in the rotating gear sleeve 23, and the outer guide column 243 is rotatably disposed in the fixed wheel 26. The outer end surface of the guide ring 242 is slidably matched with the inner end surface of the fixed wheel 26. The connecting column 244 is inserted into the inner hole of the differential rotating disk 27 and is fixedly connected to the differential rotating disk 27 by a radial set screw 28. Figure 2 As shown, a locking mechanism 2 30 is provided on the sleeve-shaped right arm end 012 of the U-shaped main ruler frame for locking the micro-motion measuring anvil 22 .

[0023] like Figure 3 As shown, both sides of the U-shaped main ruler frame 01 are wrapped with insulation sheets 013 to isolate the human body temperature during measurement.

[0024] In the specific implementation of this embodiment, a manual knob is provided at the outer end of the differential dial 27, and a force measuring device 29 is also provided at the outer end of the manual knob; like Figure 4 As shown, in this embodiment, the structure of the universal spiral measuring mechanism includes a micrometer screw 11, a fixed sleeve 12, a differential cylinder 13, a force measuring device (a ratchet) 14, etc., and a locking mechanism 15 is provided. The structure of this part is exactly the same as the structure of the upper right part of the conventional spiral micrometer measuring frame, and no further detailed description is given.

[0025] Working principle of the present invention: Hold the main scale frame still, and rotate the differential dial 27 clockwise for one circle through the manual knob or force measuring device 29, driving the planetary carrier 24 to rotate clockwise for one circle, and the planetary carrier drives the coaxial planetary gear set 25 to revolve clockwise for one circle. Under the action of the fixed inner teeth on the inner ring of the fixed wheel 26, the planetary gear 2 252 rotates counterclockwise by 40 teeth. Because the planetary gear 1 25 and the planetary gear 2 252 in the coaxial planetary gear set 25 are coaxially fixed and have the same number of teeth, the planetary gear 1 251 will drive the rotating gear sleeve 23 to rotate, and the rotating gear sleeve 23 also rotates counterclockwise by 40 teeth relative to the planetary carrier 24. The rotating gear sleeve 23 is provided with 41 teeth, with a 1-tooth difference. Then, rotate the differential dial 27 clockwise for one circle through the manual knob or force measuring device 2 29, and the rotating gear sleeve 23 will rotate clockwise by 1 tooth relative to the frame. It can also be considered that the planet carrier 24 is fixed and does not rotate, and the fixed wheel 26 rotates counterclockwise relative to the planet carrier for one circle. Then, the fixed inner teeth (40 teeth in the example) of the inner ring of the fixed wheel 26 drive the planetary wheel 2 252 to rotate counterclockwise by 40 teeth. Because the planetary wheel 1 25 in the coaxial planetary wheel set 25 is coaxially fixed with the planetary wheel 2 252 and has the same number of teeth, the planetary wheel 1 251 will drive the rotating gear sleeve 23 to rotate counterclockwise by 40 teeth relative to the planetary carrier 24. The rotating gear sleeve 23 is provided with 41 teeth, that is, the rotating gear sleeve 23 does not rotate counterclockwise relative to the planetary carrier 24 by one circle, but one tooth. That is, the differential dial 27 is rotated clockwise by one circle through the manual knob or the force measuring device 2 29, and the rotating gear sleeve 23 rotates clockwise by 1 tooth relative to the fixed wheel 26.

[0026] When measuring, routine measurements: Adjust the differential cylinder 13 of the universal spiral measuring mechanism to the 0 scale position and lock the mechanism 15.

[0027] The differential turntable 27 is rotated by the force measuring device 29 to adjust the position of the micro-motion anvil 22 so that the end of the micro-motion anvil 22 contacts the end of the micro-measuring screw 11 (sometimes a measuring rod of standard length is required, which is conventional), and the micro-motion anvil 22 is locked by the locking mechanism 2 30.

[0028] After zeroing, the measuring instrument can be used as a screw micrometer of conventional accuracy. The measured value is read directly by adjusting the differential cylinder 13. The measurement accuracy is 0.01 mm, and one more digit can be estimated on this basis.

[0029] High-precision measurement: Take the measurement of 6205 B (P2) grade bearings as an example. Its outer diameter should be between Φ52.000-52.006.

[0030] The above zero calibration process is performed first, and the micro-motion anvil 22 is locked by the locking mechanism 2 30 .

[0031] Turn on the digital display module 31 and perform zero calibration.

[0032] Place a 52 mm long standard gauge block between the micro-anvil 22 and the micrometer screw 11, rotate the differential cylinder 13 through the ratchet force knob 14, adjust the rod end of the micrometer screw 11 to contact the standard gauge block, and then lock the micrometer screw 11 through the locking mechanism 15.

[0033] The locking mechanism 2 30 is released to unlock the micro-motion anvil 22 .

[0034] Rotate the differential turntable 27 counterclockwise (from right to left) for one circle (determined according to actual needs). (One circle of the differential turntable corresponds to the micro-motion anvil 22 moving back 0.0125 mm. The maximum outer diameter of the bearing to be tested is 52.006) Place the bearing to be measured between the micro-motion anvil 22 and the micro-measuring screw 11, turn the differential dial 27 clockwise through the ratchet force measuring knob 29, adjust the position of the micro-motion anvil 22, and make the end face of the micro-motion anvil 22 contact with the outer diameter surface of the bearing, and read the reading directly through the digital display module. The reading plus the value of the 52 mm standard gauge block is the actual measurement value of the bearing.

[0035] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A digital length measuring instrument, characterized in that: It comprises a U-shaped main scale frame (01), wherein one end of the U-shaped main scale frame (01) is provided with a universal spiral measuring mechanism, and the other end is provided with a digital display spiral measuring mechanism; The digital display spiral measuring mechanism comprises a fixed screw sleeve (21), a micro-motion measuring anvil (22), a rotating gear sleeve (23), a planetary carrier (24), a fixed wheel (26), a differential rotary disk (27) and a digital display module (31); one end of the fixed screw sleeve (21) is fixedly connected to a sleeve at a right arm end (012) of a U-shaped main scale frame (01), and the other end is threadedly connected to the rotating gear sleeve (23); one end of the planetary carrier (24) is rotationally connected to the rotating gear sleeve (23) through a coaxial planetary gear set (25), and the other end is rotationally arranged in the fixed wheel (26) and inserted into the differential rotary disk (27) and coaxially rotationally connected to the outer end of the fixed wheel (26); a differential scale line is provided on the large outer cylindrical surface of the differential rotary disk 27, and the fixed screw sleeve (21) is provided with a digital display module (31); The micro-motion measuring anvil (22) slides through the fixed screw sleeve (21) and extends into the groove of the U-shaped main scale frame (01).

2. The digital length measuring instrument according to claim 1, characterized in that: The outer end of the differential rotating disk (27) is provided with a manual knob, and a second force measuring device (29) is also provided at the outer end of the manual knob.

3. The digital length measuring instrument according to claim 1, characterized in that: A fixing sleeve (211) connected to the right arm end (012) is provided at one end of the fixing screw sleeve (21), and an internal thread (212) matching the external thread of the rotating gear sleeve (23) is provided inside the fixing screw sleeve (21).

4. The digital length measuring instrument according to claim 1, characterized in that: An internal gear is provided in the rotating gear sleeve (23); one end of the coaxial planetary gear set (25) is provided with a planetary gear 1 (251) meshing with the internal gear, and the other end is provided with a planetary gear 2 (252) meshing with the internal gear of the fixed wheel (26).

5. The digital length measuring instrument according to claim 4, characterized in that: The number of teeth of the internal gear in the rotating gear sleeve (23) is one more than the number of teeth of the internal gear in the fixed wheel (26).

6. The digital length measuring instrument according to claim 4, characterized in that: The number of teeth of the planetary gear one (251) and the number of teeth of the planetary gear two (252) are equal.

7. The digital length measuring instrument according to claim 1, characterized in that: The planet carrier (24) comprises a coaxial inner guide column (241), a guide ring (242), an outer guide column (243) and a connecting column (244); the inner guide column (241) is rotatably disposed in the rotating gear sleeve (23); the outer guide column (243) is rotatably disposed in the fixed wheel (26); the outer end surface of the guide ring (242) is slidably matched with the inner end surface of the fixed wheel (26); the connecting column (244) is inserted into the inner hole of the differential rotating disk 27 and is fixedly connected to the differential rotating disk (27) via a radial set screw (28).

8. The digital length measuring instrument according to claim 1, characterized in that: A second locking mechanism (30) is provided on the sleeve-shaped right arm end (012) of the U-shaped main scale frame for locking the micro-motion measuring anvil (22).

9. The digital length measuring instrument according to claim 1, characterized in that: A locking mechanism (15) is provided on the sleeve-shaped left arm end (011) of the U-shaped main scale frame for locking the universal spiral measuring mechanism.

10. The digital length measuring instrument according to claim 1, characterized in that: Both sides of the U-shaped main ruler frame (01) are wrapped with heat-insulating sheets (013) for isolating human body temperature during measurement.

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