Length measuring instrument

Abstract

The utility model discloses a length measuring instrument, which comprises a main measuring frame, a conventional micrometer, a double-helix micrometric screw and a movable measuring frame, and is characterized in that the conventional micrometer comprises a conventional micrometric screw arranged on a third through hole and a first rotation driving group used for driving the conventional micrometric screw; the double-helix micrometric screw comprises a left-section helix section, a middle-section cylinder and a right-section helix section which are coaxially arranged in sequence, and the left-section helix section and the right-section helix section have the same rotation direction and different screw pitches; the left spiral section is connected into the third screw shaft sleeve in a threaded mode, and the right spiral section is connected with a second rotation driving set used for driving the right spiral section. The movable measuring frame is connected to the periphery of the left end of the third screw shaft sleeve in a sleeved mode, the movable measuring frame is connected with the second through hole in a sliding mode through a guide shaft, the movable measuring frame is connected with a measuring anvil coaxial with the conventional micrometric screw, and a measuring containing space is formed between the measuring anvil and the conventional micrometric screw. According to the invention, extremely high measurement precision can be realized, and the measurement efficiency and accuracy are greatly improved.

Description

Technical Field

[0001] The present application relates to the technical field of measuring devices, and in particular to a length measuring instrument. 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 0.5 mm, and the periphery of the movable sleeve is divided into 50 equal parts. The reading corresponding to each grid is 0.01 mm. If 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.

[0004] In addition, it is also necessary to ensure the efficiency of measurement during high-precision measurement. Summary of the invention

[0005] The purpose of the present application is to provide a length measuring instrument to solve the problem of low measurement accuracy in the prior art.

[0006] In order to achieve the above objectives, this application is implemented by adopting the following technical solutions:

[0007] A length measuring instrument, comprising:

[0008] The main measuring frame comprises a measuring frame body and a small measuring frame fixed to the upper right end of the measuring frame body, the small measuring frame is provided with a through hole 3, the measuring frame body is provided with a through hole 1 and a through hole 2 parallel to the through hole 3, and a screw sleeve 3 is fixed to the left end of the through hole 1;

[0009] A conventional micrometer, comprising a conventional micrometer screw disposed on a third through hole and a first rotation drive group for driving the conventional micrometer screw;

[0010] A double-helix micrometer screw, comprising a left helical segment, a middle cylinder and a right helical segment coaxially arranged in sequence, wherein the left helical segment and the right helical segment have the same rotation direction and different pitches; the left helical segment is threadedly connected in the screw sleeve three, and the right helical segment is connected to a second rotation drive group for driving the right helical segment;

[0011] A dynamic measuring frame is sleeved on the outer periphery of the left end of the screw sleeve three, and the dynamic measuring frame is slidably connected through the guide shaft and the through hole two. The dynamic measuring frame is connected to an anvil coaxial with the conventional micrometer screw, and a measuring accommodating space is formed between the anvil and the conventional micrometer screw.

[0012] Furthermore, the difference in pitch between the left and right helical segments is 0.05 mm. Furthermore, the pitch of the left helical segment is 0.50 mm-0.55 mm, and the pitch of the right helical segment is 0.05 mm smaller than that of the left helical segment.

[0013] Furthermore, the first rotation drive group and the second rotation drive group have the same structure.

[0014] Further, the second rotation drive group includes a second screw sleeve, a second differential cylinder and a second ratchet force measuring knob;

[0015] The screw sleeve 2 is fixed to the right end of the through hole 1, the right section spiral section is threadedly connected in the screw sleeve 2, the right end of the outside of the screw sleeve 2 is fixed with a fixed sleeve 2, the ratchet force measuring knob 2 is fixed to the right end of the double-helix micrometer screw, the differential cylinder 2 is sleeved on the outer periphery of the fixed sleeve 2, and is connected to the double-helix micrometer screw through the joint 2. Further, the right end of the right section spiral section is provided with a right section cylinder coaxial therewith, and the joint 2 is connected to the right section cylinder. Further, the small measuring frame is provided with a locking mechanism 1 for locking the conventional micrometer screw, and the measuring frame body is provided with a locking mechanism 2 for locking the double-helix micrometer screw. Further, a locking sleeve is also fixedly provided in the middle of the through hole 1, and the inner hole of the locking sleeve is slidably matched with the middle section cylinder; the locking sleeve is provided with a screw hole, and the end of the locking mechanism 2 passes through the measuring frame body and is threadedly connected to the screw hole of the locking sleeve. Furthermore, the right end of the guide shaft is fixedly mounted on the left end of the second through hole via a fixing sleeve, and the left end of the guide shaft is slidably matched with the dynamic measuring frame via the guide sleeve.

[0016] Furthermore, the outer side of the measuring frame body is wrapped with a heat insulating layer.

[0017] The beneficial effects of this application are:

[0018] The present application can achieve extremely high measurement accuracy through the differential design of the double-helix micrometer screw (the left and right helical segments have the same rotation direction and different pitches), and is suitable for occasions requiring extremely high accuracy;

[0019] The present application adopts a combination of conventional micrometer and double-screw micrometer principle. During measurement, the conventional micrometer screw can be used for rapid coarse adjustment, and the double-screw micrometer screw can be used for fine adjustment, which greatly improves the efficiency and accuracy of measurement.

[0020] All components of this application are integrated on the main test frame. Through ingenious design, the portability and convenience of operation of the instrument are guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall structure of the measuring instrument for this application;

[0022] Figure 2 This is a partial structural cross-sectional view of the measuring instrument of this application;

[0023] Figure 3 This is an exploded view of the measuring instrument for this application.

[0024] Among them: main measuring frame 01, dynamic measuring frame 02, measuring anvil 03, conventional micrometer screw 04, fixed sleeve 1 06, differential cylinder 1 07, gasket 10, ratchet force measuring knob 1 11, locking mechanism 1 12, double helix micrometer screw 14, screw sleeve 2 15, fixed sleeve 2 16, differential cylinder 2 17, joint 2 19, gasket 2 20, ratchet force measuring knob 2 21, locking mechanism 2 22, locking sleeve 23, screw sleeve 3 24, guide shaft 25, fixed sleeve 26, guide sleeve 27, thermal insulation sheet 28, through hole 1 012, through hole 2 013, through hole 4 021, through hole 5 022, through hole 6 023, left spiral section 141, middle cylinder 142, right spiral section 143, right cylinder 144. DETAILED DESCRIPTION

[0025] In order to make the technical means, creative features, objectives and effects achieved by this application easy to understand, this application is further explained below in conjunction with specific implementation methods.

[0026] It should be noted that in the description of the present application, the directions or positional relationships indicated by the terms "front", "rear", "left", "right", "up", "down", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application rather than requiring that the present application must be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present application. The terms "front", "rear", "left", "right", "up", and "down" used in the description of the present application refer to the directions in the accompanying drawings, and the terms "inside" and "outside" refer to the directions toward or away from the geometric center of a specific component, respectively.

[0027] like Figures 1 to 3As shown, the present application discloses a length measuring instrument, including a main measuring frame 01, a conventional micrometer, a double-helix micrometer screw 14, and a dynamic measuring frame 02. The main measuring frame 01 includes a measuring frame body and a small measuring frame fixed to the upper right end of the measuring frame body. The small measuring frame is provided with a through hole 3, and the measuring frame body is provided with a through hole 1 012 and a through hole 2 013 parallel to the through hole 3. A screw sleeve 3 24 is fixed to the left end of the through hole 1 012; the conventional micrometer includes a conventional micrometer screw 04 arranged on the through hole 3 and a first rotation driving group for driving the conventional micrometer screw 04; the double-helix micrometer screw 14 includes a left section screw 24 coaxially arranged in sequence The left and right spiral sections 141, 143 have the same rotation direction and different pitches; the left spiral section 141 is threadedly connected in the screw sleeve 24, and the right spiral section 143 is connected with a second rotation drive group for driving the right spiral section 143; the dynamic measuring frame 02 is sleeved on the outer periphery of the left end of the screw sleeve 24, and the dynamic measuring frame 02 is slidably connected through the guide shaft 25 and the through hole 2 013, and the dynamic measuring frame 02 is connected with a measuring anvil 03 coaxial with the conventional micrometer screw 04, and a measuring accommodation space is formed between the measuring anvil 03 and the conventional micrometer screw 04. In the present application, the first and second rotation drive groups have the same structure, both of which are structures of existing conventional micrometers. The use process of the present application is as follows: when no measurement is performed, the measurement accommodation space between the conventional micrometer screw 04 and the anvil 03 is in the maximum state, at which time the left spiral section 141 of the double-helix micrometer screw 14 matches the thread in the screw sleeve three 24, and the right spiral section 143 is relatively stationary therewith. When measurement is required, first use the first rotation drive group to drive the conventional micrometer screw 04 to move it to the right, thereby reducing the distance between the anvil 03 and the conventional micrometer screw 04, and initially approaching the object to be measured. Subsequently, use the second rotation drive group to drive the right spiral section 143 of the double-helix micrometer screw 14. Due to the threaded connection between the left spiral section 141 and the screw sleeve three 24, the double-helix micrometer screw 14 will drive the dynamic measuring frame 02 and the anvil 03 thereon to move finely to the right, thereby achieving precise contact and measurement of the object.

[0028] Since the pitches of the left spiral segment 141 and the right spiral segment 143 are different, different displacement amplification effects can be achieved, that is, a small rotation of the right spiral segment 143 can cause a larger displacement of the anvil 03, thereby improving the measurement accuracy.

[0029] The present application is described below through specific embodiments.

[0030] Ultra-high precision length measuring instrument (see attached Figure 1 , 2, 3), consists of a main measuring frame (static measuring frame) 01, a dynamic measuring frame 02, a measuring anvil 03, a micrometer screw 04, a fixed sleeve 06, a differential cylinder 07, an adjusting nut 1, a joint 1, a gasket 10, a ratchet force measuring knob 11, a locking mechanism 12, a double-helix micrometer screw 14, a screw sleeve 2 15, a fixed sleeve 2 16, a differential cylinder 2 17, an adjusting nut 2, a joint 2 19, a gasket 20, a ratchet force measuring knob 21, a locking mechanism 22, a locking sleeve 23, a screw sleeve 3 24, a guide shaft 25, a fixed sleeve 26, a guide sleeve 27, an insulating sheet and other parts.

[0031] The main test frame 01 is an integrated structure consisting of a test frame body at the bottom and a small test frame at the upper right position.

[0032] The small measuring frame at the upper right position of the main measuring frame 01 is also provided with a micrometer screw 04, a screw shaft sleeve 1, a fixed sleeve 06, a differential cylinder 07, an adjusting nut 1, a joint 1, a gasket 10, a ratchet force knob 11, a locking mechanism 12, etc. The structure of this part on the small measuring frame is exactly the same as the structure of the upper right part of the conventional screw micrometer measuring frame, and no further detailed description is given.

[0033] An insulating sheet (layer) is also wrapped around the outside of the measuring frame body to isolate the human body temperature during measurement.

[0034] A through hole 012 and a hole 013 are parallelly arranged on the measuring frame body of the main measuring frame (01), and the directions of the through hole 012 and the hole 013 are consistent with the direction of the micrometer screw 04.

[0035] A screw sleeve 15 is fixedly provided at the right end of the through hole 012 , and an internal thread matching the right spiral thread section on the double-helix micrometer screw 14 is provided in the inner hole of the screw sleeve 15 .

[0036] On the outside and right side of the screw sleeve 2 15, there are also fixed sleeve 2 16, differential cylinder 2 17, adjusting nut 2 (not shown), joint 2 19, gasket 20, ratchet force knob 21. The structure of this part is basically the same as the structure of the upper right part of the conventional screw micrometer measuring frame, and no further detailed description is given. The difference is that the screw sleeve 2 15 here is spirally connected with a double-helix micrometer screw 14, not a conventional micrometer screw 04.

[0037] The double-helix micrometer screw 14 is composed of four coaxial sections, namely, a left helical section 141, a middle cylinder 142, a right helical section 143, and a right cylinder 144. The left helical section 141 and the right helical section 143 have the same rotation direction, and both are right-handed in the figure. The pitches of the left helical section and the right helical section are different, and there is a pitch difference between the two helices. In the figure, the pitch of the left helical section is 0.5 mm, the pitch of the right helical section is 0.45 mm, and the pitch difference between the two helices is 0.05 mm. The smaller the pitch difference, the higher the measurement accuracy.

[0038] A dynamic measuring frame 02 is movably provided at the left end of the main measuring frame 01. The dynamic measuring frame 02 and the main measuring frame 01 are positioned and guided by a screw sleeve 3 24 and a guide shaft 25.

[0039] A measuring anvil 03 is fixedly provided in a hole at the upper end 021 of the dynamic measuring frame 02 , and the measuring anvil 03 is coaxially opposite to the micrometer screw 04 .

[0040] A through hole 022 and a through hole 023 are provided in parallel below the dynamic measuring frame 02. The through hole 022 corresponds coaxially to the through hole 012 on the measuring frame body; the through hole 023 corresponds coaxially to the hole 013 on the measuring frame body;

[0041] The screw sleeve three 24 is fixedly installed in the through hole 022 of the dynamic measuring frame 02 through the left end, and the right end of the screw sleeve three 24 slides outside and extends into the left end of the through hole 012 on the measuring frame body.

[0042] An internal thread matching the left-segment spiral thread on the double-screw micrometer screw 14 is arranged in the screw sleeve 3 24 .

[0043] The right end of the guide shaft 25 is fixedly mounted on the left end of the hole 013 on the measuring frame body through a fixing sleeve 26. The left end of the guide shaft 25 is slidably matched with the through hole 023 of the dynamic measuring frame 02 through a guide sleeve 27.

[0044] A locking sleeve 23 is fixedly provided in the middle of the through hole 012 on the measuring frame body, and the inner hole of the locking sleeve 23 is slidably matched with the middle cylinder on the double-helix micrometer screw 14, and a screw hole is provided on the locking sleeve 23. A locking mechanism 22 is provided on the measuring frame body at a position corresponding to the screw hole on the locking sleeve 23, which is used to lock or unlock the double-helix micrometer screw 14.

[0045] In this example, the pitch on the micrometer screw 04 is 0.5 millimeters.

[0046] The left helical segment 141 and the right helical segment 143 on the double helical micrometer screw 14 have the same rotation direction, and are both right-handed in the figure. The pitches of the left helical segment and the right helical segment are different, and there is a pitch difference between the two helices. In the figure, the pitch of the left helical segment is 0.55 mm, the pitch of the right helical segment is 0.5 mm, and the pitch difference between the two helices is 0.05 mm. The smaller the pitch difference, the higher the measurement accuracy.

[0047] In this example, the pitch of the right spiral section on the double-helix micrometer screw 14 is 0.5 mm, which is equal to the pitch of 0.5 mm on the micrometer screw 04. Therefore, the axial scale spacing on the fixed sleeve 16 is the same as that on the fixed sleeve 1 06, both of which are 0.5 mm intervals, but the corresponding reading does not represent 0.5 mm. Because the moving measuring frame 02 and the measuring anvil 03 move 0.05 mm to the left (equal to the pitch difference) every time the differential cylinder 17 rotates counterclockwise (from right to left), that is, each grid of the axial scale on the fixed sleeve 16 corresponds to 0.05 mm. The differential cylinder 17 is also divided into 50 equal parts. Correspondingly, each grid of the circumferential scale of the differential cylinder 17 corresponds to 0.05 mm / 50=0.001 mm.

[0048] The measurement methods of this application include:

[0049] 1) Conventional measurement:

[0050] Adjust the lower differential cylinder 17 to zero scale, and lock the double-helix micrometer screw 14 through the locking mechanism 22. At this time, the position of the dynamic measuring frame 02 is fixed, and it is fixedly connected with the main measuring frame 01. At this time, it can be used as a micrometer of conventional accuracy, and the measurement value can be read directly by adjusting the differential cylinder 107. The measurement accuracy is 0.01 mm, and one more digit can be estimated on this basis.

[0051] 2) High-precision measurement

[0052] Take the measurement of 6205B (P2) grade bearings as an example. Its outer diameter should be between Φ52.000-52.006.

[0053] First, adjust the lower differential cylinder 17 to the zero scale, and lock and fix the double-helix micrometer screw 14 through the locking mechanism 22.

[0054] Place a 52 mm long standard gauge block between the anvil 03 and the micrometer screw 04, rotate the differential cylinder 07 through the ratchet force knob 11, adjust the left end of the micrometer screw 04 to contact the standard gauge block, and then lock the micrometer screw 04 through the locking mechanism 12.

[0055] The locking mechanism 22 is released to unlock the double-helix micrometer screw 14 .

[0056] Rotate differential cylinder 2 17 counterclockwise (from right to left), and it can rotate counterclockwise 1-2 circles; place the bearing to be measured between the anvil 03 and the micrometer screw 04, rotate differential cylinder 2 17 through the ratchet force knob 21 to drive the double-helix micrometer screw 14 to rotate, adjust the position of the dynamic measuring frame 02 to make a slight move, so that the anvil 03 contacts the outer diameter surface of the bearing, and read the corresponding readings of fixed sleeve 2 16 and differential cylinder 2 17. The reading plus the value of the 52mm standard gauge block is the actual measurement value of the bearing.

[0057] In order to use it conveniently and quickly, a digital display readout device can be added on this basis to facilitate reading.

[0058] This application has the following advantages:

[0059] This measuring instrument can be used as a common micrometer or as a higher precision length measuring instrument.

[0060] A double-helix micrometer screw with the same spiral direction but a slight pitch difference is used to adjust the dynamic measuring frame for slight movement. The processing technology of the screw is good, and it is easy to realize and mass produce.

[0061] Adjustment parts for high-precision measurement, such as fixed sleeve 216 and differential cylinder 217, are the same as those of conventional micrometers, and are made with mature technology, do not require special processing, can be purchased directly, and are low in cost.

[0062] A sophisticated digital readout device can be added on this basis, making it quick and easy to use.

[0063] The whole device has no parts with complex structures, which is convenient for realization and mass production.

[0064] It is known from common technical knowledge that the present application can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the above disclosed embodiments are only illustrative in all respects and are not exclusive. All changes within the scope of the present application or within the scope equivalent to the present application are included in the present application.

Claims

1. A length measuring instrument, characterized in that: include: The main measuring frame (01) comprises a measuring frame body and a small measuring frame fixed to the upper right end of the measuring frame body, the small measuring frame is provided with a through hole 3, the measuring frame body is provided with a through hole 1 (012) and a through hole 2 (013) parallel to the through hole 3, and a screw sleeve 3 (24) is fixed to the left end of the through hole 1 (012); A conventional micrometer comprises a conventional micrometer screw (04) arranged on a third through hole and a first rotation drive group for driving the conventional micrometer screw (04); A double-helix micrometer screw (14), comprising a left helical segment (141), a middle cylinder (142) and a right helical segment (143) which are coaxially arranged in sequence, wherein the left helical segment (141) and the right helical segment (143) have the same direction of rotation but different pitches; the left helical segment (141) is threadedly connected within the screw sleeve (24), and the right helical segment (143) is connected to a second rotation drive group for driving the right helical segment (143); A dynamic measuring frame (02) is sleeved on the outer periphery of the left end of the screw shaft sleeve (24), the dynamic measuring frame (02) is slidably connected to the second through hole (013) via a guide shaft (25), and a measuring anvil (03) coaxial with a conventional micrometer screw (04) is connected to the dynamic measuring frame (02), and a measuring accommodating space is formed between the measuring anvil (03) and the conventional micrometer screw (04).

2. The length measuring instrument according to claim 1, characterized in that: The pitch difference between the left spiral section (141) and the right spiral section (143) is 0.05 mm.

3. The length measuring instrument according to claim 2, characterized in that: The pitch of the left helical segment (141) is 0.50 mm-0.55 mm, and the pitch of the right helical segment (143) is 0.05 mm smaller than the pitch of the left helical segment (141).

4. The length measuring instrument according to claim 1, characterized in that: The first rotation drive group and the second rotation drive group have the same structure.

5. The length measuring instrument according to claim 4, characterized in that: The second rotation drive group comprises a second screw sleeve (15), a second differential cylinder (17) and a second ratchet force measuring knob (21); The second screw sleeve (15) is fixed at the right end of the first through hole (012), the right spiral section (143) is threadedly connected inside the second screw sleeve (15), the second fixed sleeve (16) is fixed to the right end outside the second screw sleeve (15), the second ratchet force measuring knob (21) is fixed to the right end of the double-helix micrometer screw (14), the second differential cylinder (17) is sleeved on the outer periphery of the second fixed sleeve (16), and is connected to the double-helix micrometer screw (14) through the second joint (19).

6. The length measuring instrument according to claim 5, characterized in that: The right end of the right spiral section (143) is provided with a right cylinder (144) coaxial with the right spiral section, and the second joint (19) is connected to the right cylinder (144).

7. The length measuring instrument according to claim 1, characterized in that: The small measuring frame is provided with a first locking mechanism (12) for locking a conventional micrometer screw (04), and the measuring frame body is provided with a second locking mechanism (22) for locking a double-helix micrometer screw (14).

8. The length measuring instrument according to claim 7, characterized in that: A locking sleeve (23) is also fixedly provided in the middle of the through hole 1 (012), and the inner hole of the locking sleeve (23) is slidably matched with the middle cylinder (142); a screw hole is provided on the locking sleeve (23), and the end of the locking mechanism 2 (22) passes through the measuring frame body and is threadedly connected to the screw hole of the locking sleeve (23).

9. The length measuring instrument according to claim 1, characterized in that: The right end of the guide shaft (25) is fixedly mounted on the left end of the second through hole (013) via a fixing sleeve (26), and the left end of the guide shaft (25) is slidably matched with the dynamic measuring frame (02) via a guiding sleeve (27).

10. The length measuring instrument according to claim 1, characterized in that: The outer side of the measuring frame body is wrapped with a heat insulation layer.

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