Thread ring gauge automatic grinding machine

Abstract

The present invention discloses an automatic thread ring gauge grinding machine tool, comprising a bed, an operating table, a pair of parallel linear guides mounted along the length of the operating table, a pair of floating bearing slides mounted between the two linear guides via a support plate, an axis A and an axis B mounted on the two floating bearing slides, a dynamic torque sensor mounted between the two axes A and B, a hollow three-jaw chuck mounted on axis A for mounting a thread ring gauge, an electromagnetic friction brake connected to axis B, a three-jaw chuck mounted on the bed, a grinding tool mounted at the center of the three-jaw chuck, and a linear push rod and an automatic reset mechanism mounted at one end of the operating table. The present invention can detect the magnitude of the torque applied to the thread ring gauge in real time during grinding.

Description

Technical Field

[0001] The invention belongs to the technical field of metal cutting and relates to an automatic grinding machine tool for a thread ring gauge. Background Art

[0002] A thread ring gauge is a precision measuring instrument used to determine the conformity of external threads on a workpiece. To ensure the dimensional accuracy, positional accuracy, shape accuracy, and surface quality of the thread ring gauge, thread ring gauge manufacturers must perform precision grinding. Currently, thread ring gauge grinding is primarily performed manually by an operator. Specifically, the operator grips the thread ring gauge and repeatedly engages it with a grinding rod driven by the grinding machine's spindle motor. For optimal grinding, the grinding rod is typically coated with abrasive. During manual grinding, operator experience plays a key role in the quality of the grinding. The operator relies on this experience to appropriately adjust the force applied to the ring gauge, controlling the relative rotation between the ring gauge and the grinding rod to prevent excessive grinding that would render the gauge scrapped. This manual grinding of thread ring gauges is not only slow, demanding, and inaccurate, but also prone to accidents.

[0003] A Chinese patent application (Application Number: 201610863941.7, Application Date: 2016-09-23, Title: Automatic Precision Grinding Machine for Thread Ring Gauges, Publication Number: CN107866730A, Publication Date: 2018-04-03) discloses an automatic precision grinding machine for thread ring gauges. The machine grinds thread ring gauges by manually aligning the thread ring gauge and screwing it into a grinding tool. The machine then pulls the thread ring gauge through a pneumatic clamping device mounted on a slide rail to align it with the thread ring gauge to be ground. After clamping, the machine is started. The relative rotation of the grinding tool and the pneumatic clamping device causes the thread ring gauge and the clamping device to move in the grinding direction. After stopping, manually clicking a reverse button causes the thread ring gauge to continue grinding in the reverse direction. This process is repeated to complete the grinding of the thread ring gauge. The machine rotates the main shaft in the forward direction while the thread ring gauge clamped by the pneumatic clamping device rotates in the reverse direction, improving the grinding efficiency of the thread ring gauge. However, since the grinding machine tool reverses every time it touches the travel switch, the grinding scrap rate remains high, and it is labor-intensive and material-intensive, so it has not been effectively promoted and used. Summary of the Invention

[0004] The object of the present invention is to provide an automatic thread ring gauge grinding machine tool, which can detect the magnitude of the torque applied to the thread ring gauge during the grinding process in real time.

[0005] The technical solution adopted by the present invention is that the automatic grinding machine for thread ring gauges includes a bed, an operating table is provided on the bed, a pair of parallel linear guide pairs are installed along the length direction of the operating table, a pair of floating bearing slides are installed between the two linear guide pairs through a support plate, shaft A and shaft B are respectively installed on the two floating bearing slides, a dynamic torque sensor is installed between shaft A and shaft B, a hollow three-jaw chuck is installed on shaft A, the hollow three-jaw chuck is used to clamp the thread ring gauge, an electromagnetic friction brake is connected to shaft B, a three-jaw chuck is installed on the bed, a grinding tool is installed at the center of the three-jaw chuck, and a linear push rod and an automatic reset mechanism are respectively provided at one end of the operating table.

[0006] The present invention is also characterized in that:

[0007] A limit switch A and a limit switch B are respectively provided on one side of the operating table, and the limit switch A is provided close to the grinding tool.

[0008] The grinding tool is a grinding rod.

[0009] The central axis of the electromagnetic friction brake passes through the bearing in the bearing seat on the support seat B and is connected to the shaft B through a coupling. The support seat B is connected to the automatic reset mechanism, and the telescopic end of the linear push rod is set opposite the support seat B.

[0010] The automatic reset mechanism includes a traction rope, one end of which is connected to the support base B, and the other end of the traction rope is passed around a fixed pulley to connect a weight, and the fixed pulley is installed at one end of the operating table.

[0011] The floating bearing slide includes a slide, a bearing is installed in the slide, a stopper is provided below the bearing, a spring tube is installed below the stopper, a compression spring is installed in the spring tube, a pad on the compression spring presses the stopper, and the stopper presses the bearing.

[0012] The beneficial effects of the present invention are as follows: based on a horizontal lathe, the present invention installs a linear guide pair at the right end of the machine head, and a floating bearing slide is installed on the linear guide pair. The floating bearing slide is equipped with a bearing floating device, a thread ring gauge clamping device, a torque measuring device, and an electromagnetic brake device. The thread ring gauge is clamped to the outer cylindrical surface of the ring gauge by a hollow three-jaw chuck. During the grinding process, a dynamic torque sensor and an electromagnetic friction brake work together. The dynamic torque sensor detects the torque applied to the thread ring gauge in real time and transmits the measured signal to the electromagnetic friction brake after judgment. The braking force of the electromagnetic friction brake decreases as the torque increases, thereby ensuring processing quality and reducing the generation of scrap. At the same time, through real-time detection by the dynamic torque sensor, when the torque detected by the dynamic torque sensor remains below a set minimum value during the sliding process of the guide slide hitting the travel switch twice in a row, the thread ring gauge is judged to be completely ground. The present invention can detect the magnitude of the torque applied to the thread ring gauge during the grinding process in real time, and adjust the braking force and action time of the electromagnetic friction brake accordingly, thereby controlling the relative rotation amount between the thread ring gauge and the grinding rod, and preventing the thread ring gauge from being scrapped due to excessive grinding. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is an axonometric drawing of the automatic grinding machine for thread ring gauges of the present invention;

[0014] Figure 2 This is an exploded view of parts on the thread ring gauge automatic grinding machine tool of the present invention;

[0015] Figure 3 This is an exploded view of the floating bearing slide seat parts of the thread ring gauge automatic grinding machine of the present invention;

[0016] Figure 4 It is an exploded view of the floating bearing in the automatic grinding machine for thread ring gauges of the present invention.

[0017] In the figure, 1. bed, 2. three-jaw chuck, 3. grinding tool, 4. linear guide pair;

[0018] 5-1. Limit switch A, 5-2. Limit switch B;

[0019] 6.Hollow three-jaw chuck;

[0020] 7. Floating bearing slide, 7-1. Slide, 7-2. Bearing, 7-3. Stopper, 7-4. Compression spring, 7-5. Spring cylinder, 7-6. Screw, 7-7. Nut, 7-8. Spacer;

[0021] 8. Dynamic torque sensor, 9. Electromagnetic friction brake, 10. Linear actuator;

[0022] 11. Automatic reset mechanism, 11-1. Traction rope, 11-2. Weight, 11-3. Fixed pulley;

[0023] 12. Guide cone, 13. Thread ring gauge, 14. Shaft A, 15. Shaft B, 16. Operating table, 17. Support plate, 18. Support base A, 19. Support base B. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1

[0026] The present invention is an automatic grinding machine for thread ring gauges, the structure of which is as follows: Figure 1 As shown, the machine comprises a bed 1, an operating table 16 mounted on the bed 1, a three-jaw chuck 2 mounted on one end surface of the bed 1, a grinding tool 3, a grinding rod, clamped at the center of the three-jaw chuck 2. A pair of parallel linear guide rails 4 are mounted on the operating table 16, with guide rail stops mounted at each end. A travel switch A5-1 and a travel switch B5-2 are fixed to the side of one of the linear guide rails 4, with travel switch A5-1 being located near the three-jaw chuck 2. Two symmetrically arranged floating bearing slides 7 are mounted on the guide rail sliders of the linear guide rails 4. The two floating bearing slides 7 are mounted on a support plate 17, which is provided with a support seat A18 and a support seat B19, respectively.

[0027] Example 2

[0028] On the basis of Example 1, Figure 2 、 3 As shown, two floating bearing slides 7 are respectively mounted with shafts A14 and B15. A dynamic torque sensor 8 is mounted between shafts A14 and B15. The output shafts of dynamic torque sensor 8 are connected to shafts A14 and B15 via couplings. Dynamic torque sensor 8 is fixed to support seat A18. A hollow three-jaw chuck 6 is mounted on the left end face of shaft A14. Hollow three-jaw chuck 6 sequentially clamps thread ring gauge 13 and guide cone 12. Shaft B15 is connected to the center axis of electromagnetic friction brake 9 via a coupling. Electromagnetic friction brake 9 is mounted on support seat B19. A linear actuator 10 is mounted on one end of an operating table 16. Linear actuator 10 and three-jaw chuck 2 are located at opposite ends of operating table 16. An automatic reset mechanism 11 is also provided on one end face of operating table 16. Automatic reset mechanism 11 and linear actuator 10 are located at the same end of operating table 16. The automatic reset mechanism 11 includes a fixed pulley 11-3 installed on the operating table 16, and a traction rope 11-1 is installed on the fixed pulley 11-3. One end of the traction rope 11-1 is connected to the support seat B19, and the other end of the traction rope 11-1 passes around the fixed pulley 11-3 and connects to the weight 11-2.

[0029] Example 3

[0030] On the basis of Example 2, Figure 4 As shown, the structure of the floating bearing slide 7 includes a compression spring 7-4, which is installed in a spring barrel 7-5. The spring barrel 7-5 presses against a stopper 7-3, which presses against a bearing 7-2. The bearing 7-2 is installed in the slide 7-1. During the grinding process, the bearing 7-2 squeezes the stopper 7-3, which in turn squeezes the compression spring 7-4 to float. After the bearing 7-2 floats, the compression spring 7-4 rebounds and resets it, ensuring that the thread ring gauge 13 can float during the grinding process. At the same time, the compression spring 7-4 is installed in the middle of the spring barrel 7-5, and a screw 7-6 passes through the compression spring 7-4. A spacer 7-8 is installed between the screw 7-6 and the compression spring 7-4. The screw 7-6 passes through a hole in the slide 7-1 to install a nut 7-7. The preload force of the spring 7-4 is adjusted by rotating the nut 7-7. Since different types of thread ring gauges have different torques during grinding, the spring preload force can be adjusted to accommodate various types of thread ring gauges.

[0031] When the shaft A14 and the shaft B15 are connected to the floating bearing slide 7, the shaft A14 and the shaft B15 are coaxially sleeved in the two bearings 7-2 respectively.

[0032] The present invention relates to an automatic thread ring gauge grinding machine. The operating process is as follows: During the grinding process, as the torque measured by the dynamic torque sensor 8 increases, the braking force of the electromagnetic friction brake 9 gradually decreases. When the torque value of the thread ring gauge 13 measured by the dynamic torque sensor 8 during the grinding process exceeds a set maximum value, the electromagnetic friction brake 9 is released, causing the thread ring gauge 13 to rotate along with the grinding tool 3. After the rotation direction of the grinding tool 3 is reversed, the electromagnetic friction brake 9 is re-applied to prevent the rotation of the axis A 14 and the axis B 15, thereby preventing the thread ring gauge 13 from rotating along with the grinding tool 3. By controlling the rotation direction of the grinding tool, the thread ring gauge 13 is ground. The maximum value here is obtained through extensive experimentation. If the maximum value is exceeded, the thread ring gauge is easily damaged by grinding. Therefore, when the torque value during grinding is detected to be greater than the maximum value, the electromagnetic friction brake is released, and the rotation direction of the grinding tool is changed. This effectively prevents the thread ring gauge from being damaged by grinding, thereby effectively ensuring grinding quality and reducing scrap rate.

[0033] The movements in the present invention include: the linear push rod 10 pushes the floating bearing slide 7 to move axially to the left; the spindle forward and reverse rotation drives the floating bearing slide 7 to move axially; and the automatic reset mechanism 11 drives the floating bearing slide 7 to move axially to the right.

[0034] The linear push rod 10 pushes the floating bearing slide 7 to move axially to the left. The operator first clamps the thread ring gauge 13 on the hollow three-jaw chuck 6. When the thread ring gauge 13 is not screwed into the grinding tool 3, the linear push rod 10 works to push the floating bearing slide 7 to move axially to the left, so that the thread ring gauge 13 touches the grinding tool 3, and the rotating grinding tool 3 screws the thread ring gauge 13 onto the grinding tool 3.

[0035] The lathe's three-jaw chuck 2, which clamps the grinding tool 3, rotates forward and backward, driving the floating bearing slide 7 axially. The linear actuator 10 and the grinding tool 3 operate simultaneously. When the thread gauge 13 contacts the grinding tool 3, it is screwed into the grinding tool 3 as the spindle rotates, driving the thread gauge 13 and the floating bearing slide 7 axially to the left. When the guide slider in the linear guide pair 4 contacts the left-end limit switch 5-1 or the torque measured by the dynamic torque sensor 8 exceeds the set maximum value, the grinding tool 3 rotates in the opposite direction, driving the thread gauge 13 and the floating bearing slide 7 axially to the right. When the guide slider in the linear guide pair 4 contacts the right-end limit switch 5-2 or the torque value measured by the dynamic torque sensor 8 exceeds the set maximum value, the grinding tool 3 rotates forward, driving the thread gauge 13 and the floating bearing slide 7 axially to the left. This reciprocating cycle continues.

[0036] The automatic reset mechanism 11 drives the floating bearing slide 7 to move axially to the right, and the gravity of the weight 11 - 2 drives the support plate 17 to move axially to the right.

[0037] During the grinding process of the thread ring gauge 13, the guide slider in the linear guide pair 4 starts from touching the limit switch A5-1 (or limit switch B5-2) and ends when it touches the limit switch B5-2 (or limit switch A5-1). During this period of travel, if the torque measured by the dynamic torque sensor 8 is always lower than the set minimum value, it can be determined that the grinding of the thread ring gauge 13 is completed.

Claims

1. Automatic thread ring gauge grinding machine, characterized by: The invention comprises a bed (1), an operating table (16) is provided on the bed (1), a pair of parallel linear guide rails (4) are installed along the length direction of the operating table (16), a pair of floating bearing slides (7) are installed between the two linear guide rails (4) through a support plate (17), a shaft A (14) and a shaft B (15) are respectively installed on the two floating bearing slides (7), a dynamic torque sensor (8) is installed between the shaft A (14) and the shaft B (15), a hollow three-jaw chuck (6) is installed on the shaft A (14), the hollow three-jaw chuck (6) is used to install a thread ring gauge (13), an electromagnetic friction brake (9) is connected to the shaft B (15), a three-jaw chuck (2) is installed on the bed (1), a grinding tool (3) is installed at the center of the three-jaw chuck (2), and a linear push rod (10) and an automatic reset mechanism (11) are respectively provided at one end of the operating table (16); A travel switch A (5-1) and a travel switch B (5-2) are respectively provided on one side of the operating table (16), and the travel switch A (5-1) is provided close to the grinding tool (3); The central axis of the electromagnetic friction brake (9) passes through the bearing in the bearing seat on the support seat B (19) and is connected to the shaft B (15) through a coupling. The support seat B (19) is connected to the automatic reset mechanism (11), and the telescopic end of the linear push rod (10) is arranged opposite to the support seat B (19); The automatic reset mechanism (11) includes a traction rope (11-1), one end of which is connected to a support base B (19), and the other end of which is passed around a fixed pulley (11-3) and connected to a weight (11-2), and the fixed pulley (11-3) is mounted on one end of an operating table (16); The floating bearing slide (7) comprises a slide (7-1), a bearing (7-2) is installed in the slide (7-1), a stopper (7-3) is provided below the bearing (7-2), a spring cylinder (7-5) is installed below the stopper (7-3), a compression spring (7-4) is installed in the spring cylinder (7-5), a pad (7-8) on the compression spring (7-4) presses against the stopper (7-3), and the stopper (7-3) presses against the bearing (7-2).

2. The automatic thread ring gauge grinding machine according to claim 1, characterized in that: The grinding tool (3) is a grinding rod.

Images