Straight micrometer

Abstract

The utility model discloses a straight micrometer, which comprises a measuring rod and a measuring felt arranged at one end of the measuring rod, two axial ends of the measuring rod are respectively a measuring end and a connecting end, and the measuring felt is arranged at the measuring end; the connecting piece is fixed to the connecting end, the driving lead screw is in threaded fit with the connecting piece, the shaft sleeve is arranged on the periphery of the driving lead screw and the connecting piece, the driving piece is connected with the driving end, and the limiting piece is arranged on the connecting piece to force the connecting piece to do linear motion under rotation driving of the driving lead screw. A guide straight groove extending in the axis direction of the driving lead screw is formed in the shaft sleeve, and the limiting piece protrudes out of the outer surface of the connecting piece and is in sliding fit in the guide straight groove. And a groove which extends towards the measuring end along the axis direction of the connecting end and is used for the threaded end to enter and exit is formed in the connecting end. The requirement for higher precision can be met, and the measurement stability is better.

Description

Technical Field

[0001] The utility model belongs to the technical field of measuring equipment, and in particular relates to a linear micrometer. Background Art

[0002] The linear micrometer is a special type of general measuring instrument used in geometric measuring instruments, and has a more precise measurement accuracy than the vernier caliper. Existing conventional linear micrometers generally use the screwing of the guide rod in the threaded sleeve as a driving method, but for micrometers with high repeatability and accuracy requirements, this type of micrometer has the following problems: the gap between the guide rod in the threaded sleeve and the problem of the force direction inconsistent with the measuring rod direction will cause deviations in accuracy and repeatability. Therefore, the above problems need to be avoided for the driving mechanism of the high-precision micrometer. This utility model is derived from this. Utility Model Content

[0003] In view of at least one of the above-mentioned technical problems, the purpose of the utility model is to provide a linear micrometer, which directly drives the driving screw and the measuring rod by connecting the driving screw and the measuring rod through a connecting nut, thereby solving the problems of inconsistent force direction and gap between the threaded sleeve and the measuring rod.

[0004] The technical solution of the utility model is:

[0005] The utility model provides a straight-through micrometer, comprising a measuring rod and a felt disposed at one end of the measuring rod, the axial ends of the measuring rod are respectively implemented as a measuring end and a connecting end, and the felt is disposed on the measuring end of the measuring rod; the straight-through micrometer also includes a connecting piece fixed to the connecting end, a driving screw threadedly matched with the connecting piece, a sleeve disposed on the outer periphery of the driving screw and the connecting piece, a driving piece connected to the driving end of the driving screw, and a limiting piece disposed on the connecting piece to force the connecting piece to perform linear motion along the axial direction of the driving screw under the rotation drive of the driving screw; a guiding straight groove extending along the axial direction of the driving screw is formed on the sleeve, the limiting piece protrudes from the outer surface of the connecting piece and slidably fits in the guiding straight groove; a groove extending along the axial direction of the driving screw toward the measuring end is formed in the connecting end of the measuring rod for the threaded end of the driving screw opposite to the driving end to enter and exit.

[0006] Optionally, the connecting member is a connecting nut, which has a first hole and a second hole connected along the axial direction, the aperture of the first hole is larger than that of the second hole, the first hole is fixed to the connecting end of the measuring rod by interference fit, and the inner wall of the second hole is formed with an internal thread matching the external thread of the driving screw.

[0007] Optionally, the limiting member is a limit pin having one end interference fit in the outer wall of the connecting nut and the other end protruding outward along the radial direction of the connecting nut, the outer diameter of the limit pin is consistent with the width of the guide straight groove and the outer end of the limit pin is flush with the outer side of the guide straight groove or at least partially protrudes from the outer side of the guide straight groove.

[0008] Optionally, a bearing is fixed between the driving end and the threaded end of the driving screw rod, and the outer ring of the bearing is fixed on the inner wall of the sleeve.

[0009] Optionally, a limiting ring for clamping and limiting the bearing is further provided on the end of the bearing facing away from the threaded end.

[0010] Optionally, the driving end of the driving screw is a driving shaft with a non-circular cross-section, and the driving member includes at least a driving ring fixed on the driving shaft and rotatable around the axis of the driving screw, and a card hole matching the shape of the driving shaft is opened in the middle of the driving ring.

[0011] Optionally, the driving member further comprises a driving sleeve which is sleeved on the outer circumference of the shaft sleeve and can rotate circumferentially relative to the shaft sleeve, the driving sleeve is fixedly connected to the driving ring and the driving ring serves as a transmission member.

[0012] Optionally, a rear end cover for limiting the drive sleeve from being separated from the bearing is further provided on the side of the drive end of the drive screw facing away from the measuring rod.

[0013] Optionally, the rear end cover is fixed to the driving end of the driving screw by screws.

[0014] Optionally, the cross-section of the driving shaft is square, and the clamping hole is also square.

[0015] Compared with the prior art, the advantages of the utility model are:

[0016] The utility model relates to a linear micrometer, in which a limit piece is fixed on the connecting piece and the limit piece protrudes from the outer surface of the connecting piece and slidingly cooperates with a guide straight groove on a shaft sleeve on the periphery of the connecting piece. The limit piece is used to force the connecting piece to make a linear motion along the axial direction of the driving screw under the rotation drive of the driving screw. Through the cooperation of the limit piece and the guide straight groove, the connecting piece can only make a linear motion relative to the driving screw and will not make a circumferential rotation around the driving screw, thereby ensuring the linear motion of the measuring rod and preventing axial movement, ensuring that the force application direction is consistent with the direction of the measuring rod, being able to meet higher precision requirements and having better measurement stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0018] Figure 1 It is a structural schematic diagram of a straight-through micrometer according to an embodiment of the utility model;

[0019] Figure 2 for Figure 1 The schematic diagram of the structure of the linear micrometer omits the drive sleeve;

[0020] Figure 3 for Figure 2 Schematic diagram of the axial section structure in the linear micrometer;

[0021] Figure 4 It is a structural schematic diagram of a shaft sleeve of a linear micrometer according to an embodiment of the utility model;

[0022] Figure 5 It is a structural schematic diagram of a measuring rod of a linear micrometer according to an embodiment of the utility model;

[0023] Figure 6 It is a structural schematic diagram of a connecting nut of a straight-through micrometer according to an embodiment of the utility model;

[0024] Figure 7 It is a structural schematic diagram of a driving screw rod of a linear micrometer according to an embodiment of the utility model;

[0025] Figure 8 It is a schematic structural diagram of a driving ring of a linear micrometer according to an embodiment of the utility model.

[0026] Among them: 10, measuring rod; 11, groove; 12, measuring end; 13, connecting end; 20, measuring felt; 30, connecting nut; 31, first hole; 32, second hole; 40, driving screw; 41, threaded end; 42, driving shaft; 50, bushing; 51, guide straight groove; 60, driving part; 61, driving ring; 611, clamping hole; 62, driving sleeve; 70, limit pin; 80, bearing; 90, limit ring; 100, rear end cover. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in combination with specific implementation methods and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the utility model. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the utility model.

[0028] See also Figures 1 to 8A linear micrometer according to an embodiment of the utility model comprises a measuring rod 10, a measuring felt 20, a connecting piece, a driving screw 40, a sleeve 50, a driving piece 60 and a limiting piece. The two axial ends of the measuring rod 10 are respectively implemented as a measuring end 12 and a connecting end 13. The measuring end 12 is used to install the measuring felt 20, and the measuring felt 20 is used as a measuring surface. The measuring felt 20 is a measuring felt 20 with a T-shaped cross section, which is a conventional measuring felt 20 in the prior art. The material and structure are not described or limited, which is the prior art. The connecting piece is used to fix the connecting end 13 of the measuring rod 10 and the threaded end 41 of the driving screw 40. A groove 11 extending along the axis direction toward the measuring end 12 is provided inside the connecting end 13 of the measuring rod 10. The inner wall of the groove 11 preferably has a threaded section matching the external thread of the driving screw 40. The groove 11 can be provided for the threaded end 41 of the driving screw 40 to enter and exit therein. The depth of the groove 11 is not limited and is determined according to the measuring stroke of the measuring rod 10. The other end of the driving screw 40 opposite to the threaded end 41 is the driving end, which is used to connect with the driving member 60 so that the driving member 60 can drive the driving screw 40 to rotate around its axis. The sleeve 50 is provided on the periphery of the driving screw 40 and the connecting member, and a guide straight groove 51 extending along the axis direction thereof is provided on the sleeve 50. The limit piece is fixed on the connecting piece and the limit piece protrudes from the outer surface of the connecting piece and slides with the guide straight groove 51 on the shaft sleeve 50 outside the connecting piece. The limit piece is used to force the connecting piece to make a linear motion along the axial direction of the driving screw 40 under the rotation drive of the driving screw 40. Through the matching setting of the limit piece and the guide straight groove 51, the connecting piece can only make a linear motion relative to the driving screw 40 and will not make a circumferential rotation around the driving screw 40, thereby ensuring the linear motion of the measuring rod 10 and preventing the axial movement, ensuring that the force direction is consistent with the direction of the measuring rod 10, and solving the problem of the gap between the shaft sleeve 50 and the measuring rod 10 and the inconsistency between the force direction and the measuring rod 10 affecting the measurement accuracy.

[0029] Specifically, Figure 3 As shown, the connecting member in the embodiment of the present invention is preferably a connecting nut 30 having an outer diameter smaller than the inner wall of the sleeve 50. More specifically, as Figure 6 As shown, the connecting nut 30 has a first hole 31 and a second hole 32 which are connected along the axial direction thereof, and the aperture of the first hole 31 is larger than that of the second hole 32. In other words, a stepped countersunk hole is provided in the connecting nut 30. The first hole 31 is fixed together with the connecting hole of the measuring rod 10 by interference fit, and the inner wall of the second hole 32 is formed with an internal thread which matches the external thread of the driving screw 40. The structure is simple, the processing is convenient and the cost is low.

[0030] like Figure 2As shown, the limiting member is a stop pin 70 with one end interference fit in the outer wall of the connecting nut 30 and the other end protruding outward along the radial direction of the connecting nut 30. The outer diameter of the stop pin 70 is consistent with the width of the guide straight groove 51, and the outer end of the stop pin 70 is flush with the outer surface of the guide straight groove 51 or at least partially protrudes from the outer surface of the guide straight groove 51. It is sufficient to ensure that the stop pin 70 will not easily fall out of the guide straight groove 51 during the sliding process. As an alternative embodiment, the stop member can also be other components known to those skilled in the art that have similar functions to the stop pin 70 and can realize the linear motion of the connecting nut 30.

[0031] like Figure 3 and Figure 7 As shown, the driving end of the driving screw 40 is also as shown in Figure 7 The right end and the threaded end 41 shown are also as shown in FIG. Figure 7 A bearing 80 is also fixed between the left ends shown, that is, a smooth rod section (not marked) is provided between the threaded end 41 of the drive screw 40 and the drive end, and the bearing 80 is fixed on the smooth rod section and the outer ring of the bearing 80 is fixed together with the inner wall of the sleeve 50 to support and reduce the rotation resistance of the drive screw 40.

[0032] like Figure 3 As shown, at the end of the bearing 80 facing away from the threaded end 41, that is, Figure 3 The right end shown is also provided with a limiting ring 90 for clamping and limiting the bearing 80. The limiting ring 90 can be selected as a U-shaped limiting ring 90.

[0033] According to some embodiments of the present invention, Figure 7 As shown, the driving end of the driving screw 40 is a non-circular driving shaft 42 in the cross section, and the driving member 60 includes at least a driving ring 61 fixed on the driving shaft 42 and capable of rotating around the axis of the driving screw 40, and a clamping hole 611 matching the shape of the driving shaft 42 is provided in the middle of the driving ring 61. Preferably, the driving shaft 42 is a square shaft, and the clamping hole 611 is also a square hole of matching size. As an alternative embodiment, the driving shaft 42 can also be in other shapes such as polygons such as pentagons, hexagons, etc., and the corresponding clamping hole 611 is also in pentagons, hexagons, etc.

[0034] According to some preferred embodiments of the present invention, Figure 1 and Figure 3 and Figure 8As shown, the driving member 60 may include, in addition to the driving ring 61, a driving sleeve 62 which is sleeved on the outer periphery of the shaft sleeve 50 and connected to the driving ring 61 and can rotate around the shaft sleeve 50 in the circumferential direction. In this case, the driving ring 61 serves as a transmission member. When the driving sleeve 62 and the driving ring 61 are used as the driving member 60, the operation of the driving sleeve 62 has a larger contact area than that of the single driving ring 61, and the operation is more labor-saving.

[0035] According to some preferred embodiments of the present invention, Figures 1 to 3 As shown, at the driving end of the driving screw 40 facing away from the measuring rod 10, that is, Figure 1 The rear end cover 100 is also provided on the right side for limiting the drive sleeve 62 from being separated from the bearing 80. The radial length of the rear end cover 100 is greater than the radial length of the drive sleeve 62. The rear end cover 100 can limit the rotation position of the drive sleeve 62 to prevent the drive sleeve 62 from axially moving and separating from the shaft sleeve 50 when rotating. Figure 3 As shown, the rear end cover 100 can be fixed to the driving end of the driving screw 40 by a fastening screw.

[0036] When the linear micrometer of the embodiment of the utility model is used, the drive sleeve 62 or the drive ring 61 is rotated by hand to make the drive screw 40 rotate circumferentially around its axis, and the connecting nut 30 is threadedly matched with the drive screw 40 and the connecting thread is slidably matched on the guide straight groove 51 on the sleeve 50 through the limit pin 70, so the circumferential rotation freedom of the connecting nut 30 is limited and can only move along the axis direction of the drive screw 40 under the guidance of the guide straight groove 51, and the connecting nut 30 is fixed to the measuring rod 10, and then the linear movement of the connecting nut 30 will drive the measuring rod 10 to move linearly. It can solve the problem of low measurement accuracy caused by the gap of the guide rod in the threaded sleeve and the inconsistent direction of the measuring rod 10 in the driving mode of the micrometer in the prior art, and can meet higher accuracy requirements and have better measurement stability.

[0037] It should be noted that in order to further improve the stability of the measurement, it can be achieved by reducing the thread pitch of the threaded end 41 of the driving screw 40. The thread pitch of the threaded end 41 in the embodiment of the utility model is not specifically limited, and technical personnel in this field can choose the design according to the accuracy required for the actual measurement.

[0038] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation on the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the claims attached to the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the attached claims, or the equivalent forms of such scope and boundaries.

Claims

1. A linear micrometer, comprising a measuring rod and a measuring felt provided at one end of the measuring rod, characterized in that: The axial ends of the measuring rod are respectively implemented as measuring ends and connecting ends, and the measuring felt is arranged on the measuring end of the measuring rod; the linear micrometer also includes a connecting piece fixed to the connecting end, a driving screw threadedly matched with the connecting piece, a sleeve arranged on the periphery of the driving screw and the connecting piece, a driving piece connected to the driving end of the driving screw, and a limiting piece arranged on the connecting piece to force the connecting piece to perform linear motion along the axial direction of the driving screw under the rotation drive of the driving screw; a guiding straight groove extending along the axial direction of the driving screw is opened on the sleeve, and the limiting piece protrudes from the outer surface of the connecting piece and slidably fits in the guiding straight groove; a groove extending along its axial direction toward the measuring end is opened in the connecting end of the measuring rod for the threaded end of the driving screw opposite to the driving end to enter and exit.

2. The linear micrometer according to claim 1, characterized in that: The connecting piece is a connecting nut, which has a first hole and a second hole connected along its axial direction. The aperture of the first hole is larger than that of the second hole. The first hole is fixed to the connecting end of the measuring rod by interference fit, and the inner wall of the second hole is formed with an internal thread that matches the external thread of the driving screw.

3. The linear micrometer according to claim 2, characterized in that: The limiting member is a limit pin with one end interference fit in the outer wall of the connecting nut and the other end protruding outward along the radial direction of the connecting nut. The outer diameter of the limit pin is consistent with the width of the guide straight groove and the outer end of the limit pin is flush with the outer side of the guide straight groove or at least partially protrudes from the outer side of the guide straight groove.

4. The linear micrometer according to any one of claims 1 to 3, characterized in that: A bearing is also fixed between the driving end and the threaded end of the driving screw rod, and the outer ring of the bearing is fixed on the inner wall of the shaft sleeve.

5. The linear micrometer according to claim 4, characterized in that: A limiting ring for clamping and limiting the bearing is also provided on the end of the bearing facing away from the threaded end.

6. The linear micrometer according to claim 5, characterized in that: The driving end of the driving screw is a driving shaft with a non-circular cross-section. The driving member at least includes a driving ring fixed on the driving shaft and rotatable around the axis of the driving screw. A card hole matching the shape of the driving shaft is opened in the middle of the driving ring.

7. The linear micrometer according to claim 6, characterized in that: The driving member also includes a driving sleeve which is sleeved on the outer circumference of the shaft sleeve and can rotate circumferentially relative to the shaft sleeve. The driving sleeve is fixedly connected to the driving ring and the driving ring serves as a transmission member.

8. The linear micrometer according to claim 7, characterized in that: A rear end cover for limiting the drive sleeve from being separated from the bearing is also provided on the side of the drive end of the drive screw rod facing away from the measuring rod, and the radial length of the rear end cover is greater than the radial length of the drive sleeve.

9. The linear micrometer according to claim 8, characterized in that: The rear end cover is fixed to the driving end of the driving screw rod by screws.

10. The linear micrometer according to claim 6, characterized in that: The cross section of the driving shaft is square, and the clamping hole is also square.

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