A differential head and precision measurement device
By employing thread designs with different pitches and helical directions in the micrometer head, combined with guides and grooves to restrict rotation, the problems of low measurement accuracy and friction damage in the micrometer head are solved, resulting in a high-precision and miniaturized measuring device.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGHAI MEASURING & CUTTING TOOLS CO LTD
- Filing Date
- 2025-07-08
- Publication Date
- 2026-06-16
AI Technical Summary
Existing micrometers have low measurement accuracy, making it difficult to meet the requirements of high-precision measurement. Furthermore, the moving anvil rotates during linear movement, which increases friction and damages the workpiece and the moving anvil.
By using threads with different pitches and helical directions on the fixed and movable bushings, and through the cooperation of the micrometer screw and the differential sleeve, the linear motion of the movable anvil is achieved, its rotation is restricted, friction is reduced, and relative rotation is restricted by the guide and the slide, thereby improving measurement accuracy.
The measurement accuracy of the differential head is improved, the friction between the moving anvil and the workpiece is reduced, the possibility of damage is reduced, and higher measurement accuracy and device miniaturization are achieved.
Smart Images
Figure CN224365460U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of measuring instrument technology, and in particular to a differential head and precision measuring device. Background Technology
[0002] The information disclosed in this background section is intended only to enhance the understanding of the general background of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art.
[0003] Differential heads are an important component of many precision measuring devices. They employ the principle of a screw pair, converting the rotational motion of the differentiating sleeve into the linear motion of the movable anvil via a micrometer screw, thus facilitating precision measurement. However, current differential heads have relatively low measurement accuracy, making them unsuitable for high-precision measurement scenarios. Utility Model Content
[0004] In view of this, the purpose of this application is to provide a differential head and a precision measuring device, which aims to solve the technical problem of low measurement accuracy of current differential heads.
[0005] To achieve the above objectives, the technical solution adopted in this application is as follows:
[0006] In a first aspect, embodiments of this application provide a differential head, comprising:
[0007] A fixed bushing is provided with a first internal thread;
[0008] The movable bushing is provided with a second internal thread;
[0009] The movable anvil is fixedly connected to the movable bushing and slidably connected to the fixed bushing;
[0010] A micrometer screw is inserted into the fixed bushing and the movable bushing. The micrometer screw is provided with a first external thread and a second external thread. The first external thread meshes with the first internal thread, and the second external thread meshes with the second internal thread. The helical direction of the first external thread and the helical direction of the second external thread are the same, and the pitch of the first external thread is greater than the pitch of the second external thread.
[0011] A fixing sleeve is fitted onto the outer periphery of the fixing bushing and is fixedly connected to the fixing bushing;
[0012] A differential sleeve is fitted onto the outer periphery of the fixed sleeve and is rotatably connected to the fixed sleeve. The differential sleeve is fixedly connected to the micrometer screw.
[0013] In some embodiments of the first aspect, the movable anvil passes through the fixed bushing, and the outer peripheral side of the movable anvil is slidably connected to the inner peripheral side of the fixed bushing.
[0014] In some embodiments of the first aspect, one of the outer peripheral side of the movable anvil and the inner peripheral side of the fixed bushing is provided with a groove, and the other is provided with a guide member passing through the groove to restrict the relative rotation of the movable anvil and the fixed bushing.
[0015] In some embodiments of the first aspect, the outer periphery of the movable anvil is provided with the groove, the groove wall is a first conical surface, the inner periphery of the fixed bushing is provided with the guide member, the guide member includes a connecting part and a guiding part connected to each other, the connecting part is connected to the fixed bushing, the guiding part passes through the groove, and the outer periphery of the guiding part is a second conical surface that abuts against the first conical surface.
[0016] In some embodiments of the first aspect, the movable bushing includes a through portion and a threaded portion connected together, the threaded portion being provided with a second internal thread, the movable anvil being provided with a connecting hole at one end near the differential sleeve, the through portion passing through the connecting hole and being bonded to the hole wall of the connecting hole.
[0017] In some embodiments of the first aspect, the differential head further includes an elastic sleeve, which passes through the differential sleeve and is fixedly connected to the micrometer screw, wherein the differential sleeve and the elastic sleeve are interference-fitted.
[0018] In some embodiments of the first aspect, the micrometer further includes a threaded fastener and a washer, the threaded fastener including a nut and a fastening screw connected together, the washer located at the end of the resilient sleeve away from the movable anvil, the fastening screw passing through the washer and the resilient sleeve and threadedly connected to the micrometer screw, and the washer abutting against the resilient sleeve and the nut respectively.
[0019] In some embodiments of the first aspect, a first slit is provided through the fixed bushing, the position of the first slit corresponding to the position of the first internal thread, and the micrometer head further includes a first adjusting sleeve, the first adjusting sleeve being sleeved on the outer peripheral side of the fixed bushing, and the inner peripheral side of the first adjusting sleeve being threadedly connected to the outer peripheral side of the fixed bushing.
[0020] In some embodiments of the first aspect, a second slit is provided through the movable bushing, the position of the second slit corresponding to the position of the second internal thread, and the micrometer head further includes a second adjusting sleeve, the second adjusting sleeve being sleeved on the outer peripheral side of the movable bushing, and the inner peripheral side of the second adjusting sleeve being threadedly connected to the outer peripheral side of the movable bushing.
[0021] Secondly, embodiments of this application provide a precision measuring device, including the differential head described in any of the embodiments of the first aspect above.
[0022] The beneficial effects of this application are as follows:
[0023] The micrometer head provided in this application has a first internal thread on a fixed bushing and a second internal thread on a movable bushing. The movable anvil is fixedly connected to the movable bushing and slidably connected to the fixed bushing. A micrometer screw passes through the fixed bushing and the movable bushing. The micrometer screw has a first external thread that meshes with the first internal thread and a second external thread that meshes with the second internal thread. The helical direction of the first external thread is the same as that of the second external thread, and the pitch of the first external thread is greater than that of the second external thread. A fixed sleeve is fitted on the outer circumference of the fixed bushing and is fixedly connected to the fixed bushing. A micrometer sleeve is fitted on the outer circumference of the fixed sleeve and is rotatably connected to the fixed sleeve. The micrometer sleeve is fixedly connected to the micrometer screw.
[0024] When the differential sleeve is rotated, it drives the micrometer screw to rotate, causing the micrometer screw to move relative to the fixed bushing in a first direction. Since the helical direction of the first external thread is the same as that of the second external thread, and the pitch of the first external thread is greater than that of the second external thread, the micrometer screw can drive the movable bushing to move in a second direction opposite to the first direction during its rotation. This causes the movable anvil to move relative to the micrometer screw in the second direction, thus reducing the actual movement of the movable anvil and helping to improve the measurement accuracy of the differential head.
[0025] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This paper shows a schematic diagram of the differential head from one perspective in an embodiment of this application;
[0028] Figure 2 This illustrates another perspective structural diagram of the differential head in an embodiment of this application;
[0029] Figure 3 It shows Figure 2 A schematic diagram of the decomposed structure;
[0030] Figure 4 This illustration shows another perspective structural diagram of the differential head in an embodiment of this application;
[0031] Figure 5 It shows Figure 4 Schematic diagram of the cross-sectional structure at point AA;
[0032] Figure 6 A schematic diagram of the micrometer screw in an embodiment of this application is shown;
[0033] Figure 7 A schematic diagram of the guide component in an embodiment of this application is shown;
[0034] Figure 8 A schematic diagram of the structure of the movable anvil in an embodiment of this application is shown;
[0035] Figure 9 A schematic diagram of the structure of the movable bushing in an embodiment of this application is shown;
[0036] Figure 10 A schematic diagram of the fixed sleeve in an embodiment of this application is shown.
[0037] Explanation of key component symbols:
[0038] 100 - Micrometer head; 110 - Fixed bushing; 111 - First internal thread; 112 - First slit; 120 - Movable bushing; 121 - Second internal thread; 122 - Through part; 123 - Threaded part; 124 - Second slit; 130 - Movable anvil; 131 - Slide groove; 132 - First conical surface; 133 - Connecting hole; 140 - Micrometer screw; 141 - First external thread; 142 - Second external thread; 150 - Fixed sleeve; 160 - Micrometer sleeve; 170 - Guide; 171 - Connecting part; 172 - Guide part; 173 - Second conical surface; 181 - Elastic sleeve; 182 - Washer; 183 - First adjusting sleeve; 184 - Second adjusting sleeve; 190 - Threaded fastener; 191 - Nut; 192 - Fastening screw. Detailed Implementation
[0039] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0040] In the description of this application, the terms "center", "longitudinal", "lateral", "length", "width", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0041] Furthermore, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Moreover, "above" or "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below" or "below" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0042] In the description of this application, the terms "first," "second," etc., are used to distinguish different objects and should not be construed as indicating or implying a specific order or hierarchy, or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, the term "multiple" means two or more, unless otherwise explicitly specified.
[0043] In the description of this application, unless otherwise explicitly specified, the terms "installation," "connection," "attachment," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0044] In the description of this application, the term "and / or" can be understood to mean three possibilities. For example, A and / or B can represent: A alone; A and B simultaneously; or B alone. Additionally, the character " / " generally indicates that the preceding and following objects have an "or" relationship.
[0045] In the description of this application, "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" also includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering. For example, if the angle between two directions is 80° to 90°, the two directions can be considered perpendicular; if the angle between two directions is 0° to 10°, the two directions can be considered parallel.
[0046] Differential heads are an important component of many precision measuring devices. They utilize the principle of a screw pair, converting the rotational motion of the differential sleeve into the linear motion of the movable anvil via a micrometer screw, thus facilitating precision measurement. However, current differential heads have relatively low measurement accuracy, making them unsuitable for high-precision measurement scenarios. Furthermore, the simultaneous linear and rotational movement of the movable anvil increases friction between it and the workpiece, potentially damaging both.
[0047] like Figure 1 and Figure 2 As shown, in order to solve the above-mentioned technical problems, the embodiments of this application provide a micrometer head 100, which relates to the field of measuring instrument technology. It is mainly used in precision measuring devices (such as micrometers, height gauges, optical comparators, thickness gauges, etc.), and can also be used in precision machine tools, medical devices, optical instruments, etc., without specific limitations.
[0048] like Figures 3 to 6 As shown, the micrometer head 100 provided in this embodiment includes: a fixed bushing 110, a movable bushing 120, a movable anvil 130, a micrometer screw 140, a fixed sleeve 150, and a micrometer sleeve 160.
[0049] The fixed bushing 110 is provided with a first internal thread 111; the movable bushing 120 is provided with a second internal thread 121; the movable anvil 130 is fixedly connected to the movable bushing 120 and slidably connected to the fixed bushing 110; the micrometer screw 140 passes through the fixed bushing 110 and the movable bushing 120, and the micrometer screw 140 is provided with a first external thread 141 and a second external thread 142. The first external thread 141 meshes with the first internal thread 111, and the second external thread 142 meshes with the first internal thread 111. Two internal threads 121 mesh, the helical direction of the first external thread 141 is the same as that of the second external thread 142, the pitch P1 of the first external thread 141 is greater than the pitch P2 of the second external thread 142; the fixed sleeve 150 is sleeved on the outer circumference of the fixed bushing 110 and is fixedly connected to the fixed bushing 110; the differential sleeve 160 is sleeved on the outer circumference of the fixed sleeve 150 and is rotatably connected to the fixed sleeve 150, and the differential sleeve 160 is fixedly connected to the micrometer screw 140.
[0050] It should be noted that "fixed connection" can be understood as: the relative positions of two objects remain unchanged under normal use conditions, that is, there will be no easy relative movement between them; for example, a fixed connection can be a snap-fit, screw connection, abutment, welding, injection molding, adhesive, etc., without specific limitations here. "The helical direction of the first external thread 141 is the same as the helical direction of the second external thread 142" can be understood as: the helical direction of the first external thread 141 and the helical direction of the second external thread 142 are both right-handed, or the helical direction of the first external thread 141 and the helical direction of the second external thread 142 are both left-handed, without specific limitations here.
[0051] It should be noted that since the first external thread 141 meshes with the first internal thread 111, and the second external thread 142 meshes with the second internal thread 121, the first internal thread 111 and the second internal thread 121 also satisfy the above-mentioned helical direction and pitch relationship. That is, the pitch of the first internal thread 111 is also P1, and the pitch of the second internal thread 121 is also P2. The pitch P1 of the first internal thread 111 is greater than the pitch P2 of the second internal thread 121. At the same time, the helical direction of the first internal thread 111 and the helical direction of the second internal thread 121 are the same.
[0052] It is understood that in the micrometer head 100 provided in this embodiment, the first external thread 141 and the first internal thread 111 form a set of helical pairs, and the second external thread 142 and the second internal thread 121 form another set of helical pairs. When the micrometer sleeve 160 is rotated, the micrometer sleeve 160 drives the micrometer screw 140 to rotate, so that the micrometer screw 140 moves linearly in the first direction relative to the fixed bushing 110. Since the helical direction of the first external thread 141 is the same as that of the second external thread 142, and the pitch of the first external thread 141 is greater than that of the second external thread 142, during the rotation and movement of the micrometer screw 140, the movable bushing 120 can be driven to move linearly in the second direction opposite to the first direction, so as to drive the movable anvil 130 to move linearly in the second direction relative to the micrometer screw 140. This reduces the actual movement of the movable anvil 130, thereby helping to improve the measurement accuracy of the micrometer head 100.
[0053] Meanwhile, since the movable anvil 130 is slidably connected to the fixed bushing 110, the relative rotation between the movable anvil 130 and the fixed bushing 110 is restricted, so that the movable anvil 130 only makes linear motion under the drive of the differential sleeve 160. This reduces the friction between the movable anvil 130 and the workpiece to be measured, thereby reducing the possibility of damage to the movable anvil 130 and the workpiece to be measured.
[0054] like Figure 1 , Figure 2 and Figure 10As shown, to facilitate understanding of the improved measurement accuracy of the micrometer head 100, it is assumed that the pitch difference between the first external thread 141 and the second external thread 142 is 0.05mm, i.e., P1-P2=0.05mm. One rotation of the micrometer sleeve 160 causes the micrometer screw 140 to move linearly 0.5mm relative to the fixed bushing 110 along the first direction. At this time, the micrometer screw 140 also causes the movable anvil 130 to move linearly 0.45mm relative to the micrometer screw 140 along the second direction, thus achieving an actual movement of 0.5mm-0.4mm for the movable anvil 130. 5mm = 0.05mm. The differential sleeve 160 has fifty equal divisions along its circumference (secondary scale), so its graduation value is 0.001mm, that is, each division is 0.001mm. The fixed sleeve 150 has 10 divisions of 0.0001mm each of its circumference horizontal scale (vernier scale). The fixed sleeve 150 has 50 divisions of 0.05mm each of its axial longitudinal scale (main scale). Therefore, the measuring range of the differential head 100 is 0mm to 2.5mm, and the reading = main scale reading + secondary scale reading + vernier scale reading. Of course, the pitch difference between the first external thread 141 and the second external thread 142 can be set to other values according to requirements, and no specific limitation is made here.
[0055] like Figure 4 and Figure 5 As shown, in some embodiments, the movable anvil 130 passes through the fixed bushing 110, that is, at least a portion of the movable anvil 130 is accommodated within the fixed bushing 110, and the outer peripheral side of the movable anvil 130 is slidably connected to the inner peripheral side of the fixed bushing 110. This not only restricts the rotation of the movable anvil 130 relative to the fixed sleeve 150, but also reduces the radial dimension of the micrometer head 100, which helps to miniaturize the design of the micrometer head 100.
[0056] like Figure 4 and Figure 5 As shown, further, a groove 131 is provided on one of the outer peripheral side of the movable anvil 130 and the inner peripheral side of the fixed bushing 110, and a guide 170 is provided on the other, the guide 170 passing through the groove 131.
[0057] It is understandable that by cooperating with the guide 170 and the slide 131, the relative rotation of the movable anvil 130 and the fixed bushing 110 is restricted, so that the movable anvil 130 moves linearly under the drive of the differential sleeve 160, thereby reducing the friction between the movable anvil 130 and the workpiece to be measured.
[0058] like Figure 5 , Figure 7 and Figure 8As shown, the movable anvil 130 is further provided with a groove 131 on its outer periphery. The groove wall of the groove 131 is a first conical surface 132. The fixed bushing 110 is provided with a guide 170 on its inner periphery. The guide 170 includes a connecting part 171 and a guide part 172 connected to each other. The connecting part 171 is connected to the fixed bushing 110. The guide part 172 passes through the groove 131. The outer periphery of the guide part 172 is a second conical surface 173 that abuts against the first conical surface 132.
[0059] For example, the connection between the connecting part 171 and the fixed bushing 110 can be a threaded connection; of course, it can also be a snap-fit, adhesive, etc., without specific limitations.
[0060] Understandably, when the differential sleeve 160 is rotated, the movable anvil 130 can move linearly under the guidance provided by the slide groove 131 and the guide part 172. The first conical surface 132 of the slide groove 131 abuts against the second conical surface 173 of the guide part 172, which can improve the smoothness and stability of the movable anvil 130 during the sliding process.
[0061] In other embodiments, one of the movable anvil 130 and the fixed bushing 110 is provided with a slider, and the other is provided with a guide rail that cooperates with the slider. This can also limit the rotation of the movable anvil 130, so that the movable anvil 130 only performs linear motion under the drive of the differential sleeve 160. Here, the specific implementation method of the sliding connection between the movable anvil 130 and the fixed bushing 110 is not limited.
[0062] like Figure 5 , Figure 8 and Figure 9 As shown, in some embodiments, the movable bushing 120 includes a through portion 122 and a threaded portion 123 connected together. The threaded portion 123 is provided with a second internal thread 121. The movable anvil 130 is provided with a connecting hole 133 at one end near the differential sleeve 160. The through portion 122 passes through the connecting hole 133 and is bonded to the hole wall of the connecting hole 133, so as to achieve a fixed connection between the movable anvil 130 and the movable bushing 120 through bonding, thereby restricting the relative movement between the movable anvil 130 and the movable bushing 120, so that the micrometer screw 140 can slide through the movable bushing 120.
[0063] In other embodiments, the fixed connection between the movable anvil 130 and the movable bushing 120 is one of snap-fit, screw connection, welding, etc., which can also limit the relative movement between the movable anvil 130 and the movable bushing 120. The specific method of fixed connection between the two is not limited here.
[0064] like Figures 3 to 5As shown, in some embodiments, the micrometer head 100 further includes an elastic sleeve 181, which passes through the micrometer sleeve 160, that is, at least a portion of the elastic sleeve 181 is housed within the micrometer sleeve 160, and the elastic sleeve 181 is fixedly connected to the micrometer screw 140. The micrometer sleeve 160 and the elastic sleeve 181 are interference-fitted, so that when the micrometer sleeve 160 is rotated, the elastic sleeve 181 rotates synchronously with the micrometer sleeve 160, thereby driving the micrometer screw 140 to rotate and move relative to the fixed bushing 110.
[0065] like Figure 3 As shown, it should be noted that the elastic sleeve 181 has a slit, which enables the elastic sleeve 181 to have elastic deformation capability, so that the elastic sleeve 181 can be interference-fitted with the differential sleeve 160 after being inserted into the differential sleeve 160.
[0066] like Figures 3 to 5 As shown, the micrometer head 100 further includes a threaded fastener 190 and a washer 182. The threaded fastener 190 includes a nut 191 and a fastening screw 192 connected together. The washer 182 is located at the end of the elastic sleeve 181 away from the movable anvil 130. The fastening screw 192 passes through the washer 182 and the elastic sleeve 181 and is threadedly connected to the micrometer screw 140. The washer 182 abuts against the elastic sleeve 181 and the nut 191 respectively. This achieves a fixed connection between the elastic sleeve 181 and the micrometer screw 140. This threaded connection method facilitates the assembly and disassembly of the micrometer head 100.
[0067] like Figures 3 to 5 As shown, in some embodiments, a first slit 112 is provided through the fixed bushing 110, the position of the first slit 112 corresponding to the position of the first internal thread 111. The micrometer head 100 also includes a first adjusting sleeve 183, which is sleeved on the outer periphery of the fixed bushing 110, and the inner periphery of the first adjusting sleeve 183 is threadedly connected to the outer periphery of the fixed bushing 110. In this way, by rotating the first adjusting sleeve 183, the tightness of the fixed bushing 110 can be adjusted, which helps to optimize the operating feel and facilitates the assembly and disassembly of the micrometer screw 140 and the fixed bushing 110.
[0068] like Figure 4 , Figure 5 and Figure 9As shown, in some embodiments, a second slit 124 is provided through the movable bushing 120, the position of the second slit 124 corresponding to the position of the second internal thread 121. The micrometer head 100 also includes a second adjusting sleeve 184, which is sleeved on the outer periphery of the movable bushing 120, and the inner periphery of the second adjusting sleeve 184 is threadedly connected to the outer periphery of the movable bushing 120. In this way, by rotating the second adjusting sleeve 184, the tightness of the movable bushing 120 can be adjusted, which helps to optimize the operating feel and facilitates the assembly and disassembly of the micrometer screw 140 and the movable bushing 120.
[0069] To address the aforementioned technical problems, embodiments of this application also provide a precision measuring device, including the differential head 100 from any of the above embodiments.
[0070] It is understood that since the precision measuring device provided in this embodiment has the differential head 100 in any of the above embodiments, it has all the beneficial effects of the differential head 100, which will not be described in detail here.
[0071] In the description of this application, the terms "some embodiments," "one embodiment," "example," "specific example," "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In the description of this application, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0072] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. A differentiating head, characterized in that, include: The fixed bushing (110) is provided with a first internal thread (111); The movable bushing (120) is provided with a second internal thread (121); The movable anvil (130) is fixedly connected to the movable bushing (120) and slidably connected to the fixed bushing (110); A micrometer screw (140) is inserted into the fixed bushing (110) and the movable bushing (120). The micrometer screw (140) is provided with a first external thread (141) and a second external thread (142). The first external thread (141) meshes with the first internal thread (111), and the second external thread (142) meshes with the second internal thread (121). The helical direction of the first external thread (141) and the helical direction of the second external thread (142) are the same. The pitch of the first external thread (141) is greater than the pitch of the second external thread (142). A fixed sleeve (150) is fitted onto the outer periphery of the fixed bushing (110) and is fixedly connected to the fixed bushing (110); The differential sleeve (160) is sleeved on the outer periphery of the fixed sleeve (150) and rotatably connected to the fixed sleeve (150). The differential sleeve (160) is fixedly connected to the micrometer screw (140).
2. The differential head according to claim 1, characterized in that, The movable anvil (130) is inserted through the fixed bushing (110), and the outer peripheral side of the movable anvil (130) is slidably connected to the inner peripheral side of the fixed bushing (110).
3. The differential head according to claim 2, characterized in that, One of the outer periphery of the movable anvil (130) and the inner periphery of the fixed bushing (110) is provided with a groove (131), and the other is provided with a guide (170). The guide (170) passes through the groove (131) to restrict the relative rotation of the movable anvil (130) and the fixed bushing (110).
4. The differential head according to claim 3, characterized in that, The movable anvil (130) is provided with a groove (131) on its outer periphery. The groove wall of the groove (131) is a first conical surface (132). The fixed bushing (110) is provided with a guide (170) on its inner periphery. The guide (170) includes a connecting part (171) and a guide part (172) connected to each other. The connecting part (171) is connected to the fixed bushing (110). The guide part (172) passes through the groove (131). The outer periphery of the guide part (172) is a second conical surface (173) that abuts against the first conical surface (132).
5. The differential head according to claim 1, characterized in that, The movable bushing (120) includes a through part (122) and a threaded part (123) connected to each other. The threaded part (123) is provided with a second internal thread (121). The movable anvil (130) is provided with a connecting hole (133) at one end near the differential sleeve (160). The through part (122) passes through the connecting hole (133) and is bonded to the hole wall of the connecting hole (133).
6. The differential head according to any one of claims 1 to 5, characterized in that, The micrometer head also includes an elastic sleeve (181), which passes through the micrometer sleeve (160) and is fixedly connected to the micrometer screw (140). The micrometer sleeve (160) and the elastic sleeve (181) are interference-fitted.
7. The differential head according to claim 6, characterized in that, The micrometer head also includes a threaded fastener (190) and a washer (182). The threaded fastener (190) includes a nut (191) and a fastening screw (192) connected together. The washer (182) is located at the end of the elastic sleeve (181) away from the movable anvil (130). The fastening screw (192) passes through the washer (182) and the elastic sleeve (181) and is threadedly connected to the micrometer screw (140). The washer (182) abuts against the elastic sleeve (181) and the nut (191) respectively.
8. The differential head according to any one of claims 1 to 5, characterized in that, A first slit (112) is provided through the fixed bushing (110), the position of the first slit (112) corresponds to the position of the first internal thread (111), the micro head also includes a first adjusting sleeve (183), the first adjusting sleeve (183) is sleeved on the outer peripheral side of the fixed bushing (110), and the inner peripheral side of the first adjusting sleeve (183) is threadedly connected to the outer peripheral side of the fixed bushing (110).
9. The differential head according to any one of claims 1 to 5, characterized in that, A second slit (124) is provided through the movable bushing (120), the position of the second slit (124) corresponds to the position of the second internal thread (121), the micro head also includes a second adjusting sleeve (184), the second adjusting sleeve (184) is sleeved on the outer peripheral side of the movable bushing (120), and the inner peripheral side of the second adjusting sleeve (184) is threadedly connected to the outer peripheral side of the movable bushing (120).
10. A precision measuring device, characterized in that, Includes the differential head according to any one of claims 1 to 9.