Deep blind hole grinding machine

Abstract

The utility model relates to a deep blind hole grinding machine which comprises a working table, a sliding table mechanism and a positioning tool are arranged on the working table, a spindle mechanism is arranged on the sliding table mechanism and connected with a grinding tool, the grinding tool comprises a connecting rod, one end of the connecting rod is connected with the spindle mechanism through a connector, and the other end of the connecting rod is connected with the positioning tool. A supporting sleeve is sleeved outside the connecting rod between the connector and the grinding tool, the supporting sleeve is in clearance fit with the connecting rod, and one end, facing the connector, of the supporting sleeve is connected with a positioning mechanism. The supporting sleeve extends into the blind hole, the middle of the connecting rod can be supported, the stability of the connecting rod is improved, bending deformation of the connecting rod is prevented, vibration of the connecting rod is reduced, and therefore the grinding precision is improved.

Description

Technical Field

[0001] This utility model belongs to the field of grinding equipment, and in particular a deep blind hole grinding machine. Background Technology

[0002] Some parts require the machining of deep blind holes. When the precision requirements for blind holes are high, machining methods such as turning, drilling, and boring are insufficient to meet the accuracy requirements. Therefore, after machining the basic holes, the blind holes need to be ground. When the depth of the blind holes is large, for example, when the length-to-diameter ratio is greater than 30, grinding becomes more difficult.

[0003] Utility model patent application number CN202110663873.0 discloses a grinding method and tooling for improving the roughness of deep holes in connecting rods of large diesel engines. The method includes a support guide component, a grinding wheel, a drill rod, a connecting shank, and two V-bolts. The two V-bolts are placed on a gantry milling machine, and the connecting rod is mounted on these two V-bolts. The support guide component is connected to the connecting rod to support and position the drill rod. One end of the drill rod is connected to the spindle of the gantry milling machine via the connecting shank, and the other end is connected to the grinding wheel. One end of the grinding wheel and the drill rod passes through the support guide component and extends into the deep hole. The guide sleeve, grinding wheel, drill rod, and connecting shank are coaxial with the axis of the deep hole and the X-axis of the gantry milling machine. The rotation and feed motion of the X-axis of the gantry milling machine drive the grinding wheel to grind the hole wall of the deep hole, so that the roughness of the deep hole meets the technical requirements after processing. Although the device reduces the vibration and deflection of the drill rod during machining by using a guide sleeve, the vibration reduction effect is poor because the guide sleeve is installed outside the deep hole. Since most of the drill rod is located inside the deep hole, the drill rod is unstable and prone to deformation due to its long length, making it difficult to guarantee grinding accuracy. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a deep blind hole grinding machine that can improve the stability of grinding tools and thus improve grinding accuracy.

[0005] To solve the above problems, the technical solution adopted by this utility model is as follows: a deep blind hole grinding machine, including a worktable, a slide mechanism and a positioning fixture are provided on the worktable, a spindle mechanism is provided on the slide mechanism, and a grinding tool is connected to the spindle mechanism.

[0006] The grinding tool includes a connecting rod. One end of the connecting rod is connected to the spindle mechanism through a connector. The outer wall of the other end of the connecting rod is fitted with a grinding tool. A support sleeve is fitted over the connecting rod between the connector and the grinding tool. The support sleeve and the connecting rod are in clearance fit. A positioning mechanism is connected to the end of the support sleeve facing the connector.

[0007] Furthermore, the positioning mechanism includes a slide block that slides with the worktable surface and is connected to a drive mechanism; a positioning sleeve is provided on the slide block, and a support sleeve is located inside the positioning sleeve and fixedly connected to the positioning sleeve.

[0008] Furthermore, the driving mechanism is a hydraulic cylinder.

[0009] Furthermore, a cooling medium inlet channel is provided inside the connecting rod, an inlet is provided at one end of the connecting rod located at the connector, the inlet is connected to the cooling medium inlet channel, and an outlet is provided at one end face of the connecting rod located at the grinding wheel, the outlet is connected to the cooling medium inlet channel; a cooling groove is provided on the outer wall of the grinding wheel that extends axially through the grinding wheel, and a cooling medium outlet channel is provided on the support sleeve.

[0010] Furthermore, a third sealing structure is provided on the inner wall of the end of the support sleeve facing the mold.

[0011] Furthermore, the cooling medium discharge channel includes a first tank, a second tank, and a discharge port. The first tank is located on the outer wall of the support sleeve facing the mold, and the bottom wall of the first tank is provided with multiple filter holes. The second tank is located on the inner wall of the support sleeve, and one end of the second tank is connected to the filter holes, while the other end is connected to the discharge port. The discharge port is located on the end of the support sleeve facing the connector. A first sealing structure is provided on the outer wall of the support sleeve between the discharge port and the first tank, and a second sealing structure is provided on the inner wall of the end of the support sleeve away from the mold. The second tank is located between the second sealing structure and the third sealing structure. A pressure reducing valve is provided inside the discharge port.

[0012] Furthermore, the grinding wheel is connected to the connecting rod by multiple screws.

[0013] The beneficial effects of this invention are as follows: During grinding, a conventional hole grinding tool can be used to grind the opening section of the blind hole once, with a grinding depth of 1 / 3 to 1 / 2 of the blind hole depth. Then, this invention can be used for a second grinding. During the second grinding, the support sleeve extends into the blind hole, which can support the middle part of the connecting rod, improve the stability of the connecting rod, prevent the connecting rod from bending and deforming, reduce the vibration of the connecting rod, and thus improve the grinding accuracy. Attached Figure Description

[0014] Figure 1 This is a front view schematic diagram of the grinding machine of this utility model;

[0015] Figure 2 This is a schematic diagram of the fit between the grinding tool and the support sleeve;

[0016] Figure 3 yes Figure 2 Schematic diagram of the cross section of AA;

[0017] Figure 4 yes Figure 2 Enlarged schematic diagram of part B in the middle;

[0018] Figure 5 yes Figure 2An enlarged schematic diagram of section C;

[0019] Reference numerals: 1—Connecting rod; 2—Connector; 3—Mold; 4—Support sleeve; 5—Slide; 6—Positioning sleeve; 7—Hydraulic cylinder; 8—Cooling medium inlet channel; 9—Inlet; 10—Outlet; 11—Cooling tank; 12—Cooling medium outlet channel; 121—First tank; 122—Second tank; 123—Outlet; 124—Pressure reducing valve; 125—First sealing structure; 126—Second sealing structure; 127—Third sealing structure; 100—Worktable surface; 110—Spindle mechanism; 120—Positioning fixture; 130—Slide mechanism. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] The deep blind hole grinding machine of this utility model, such as Figures 1 to 5 As shown, it includes a worktable 100, a slide mechanism 130 and a positioning fixture 120 on the worktable 100, a spindle mechanism 110 on the slide mechanism 130, and a grinding tool connected to the spindle mechanism 110.

[0022] The slide mechanism 130 can slide on the worktable 100, thereby driving the spindle mechanism 110 to move linearly. The slide mechanism 130 can be any existing slide mechanism on the machine tool. The spindle mechanism 110 includes a spindle and a grinding drive mechanism that drives the spindle to rotate, which can be achieved using existing technology.

[0023] The positioning fixture 120 is used to position the part to be ground. Common positioning methods can be used. For example, when the part is a shaft and the deep blind hole is the center hole of the shaft, a three-jaw chuck or a similar positioning mechanism can be used to clamp and position the shaft. When the part is a plate or box, a clamping positioning method is used to clamp and fix the part to the worktable 100.

[0024] The grinding tool includes a connecting rod 1. One end of the connecting rod 1 is detachably connected to the spindle mechanism 110 via a connector 2. The connector 2 can adopt an existing connection structure. The outer wall of the other end of the connecting rod 1 is fitted with a grinding tool 3. The grinding tool 3 can be connected to the connecting rod 1 by multiple screws. A support sleeve 4 is fitted over the connecting rod 1 between the connector 2 and the grinding tool 3. The support sleeve 4 is clearance-fitted with the connecting rod 1. A positioning mechanism is connected to the end of the support sleeve 4 facing the connector 2.

[0025] In this invention, a conventional grinding device and grinding process can be used to perform a first grinding of the opening section of the deep blind hole, with a grinding depth of 1 / 3 to 1 / 2 of the blind hole depth. Since the grinding depth of the first grinding is small, the difficulty is relatively low, and the grinding accuracy is controllable. Then, this grinding machine is used to perform a second grinding of the unground portion of the deep blind hole.

[0026] When performing secondary grinding on the inside of a deep blind hole, the spindle mechanism 110 drives the connecting rod 1 and the grinding wheel 3 to rotate. The grinding wheel 3 grinds the inner wall of the blind hole. The linear movement of the slide mechanism 130 drives the grinding wheel 3 to feed axially until the grinding wheel 3 reaches the bottom of the blind hole.

[0027] Because the blind hole is deep, the required length of connecting rod 1 is also large, resulting in significant overall deflection of connecting rod 1, which easily leads to bending deformation and vibration during grinding. In this invention, a support sleeve 4 is installed inside the blind hole. The support sleeve 4 supports the connecting rod 1 near the grinding wheel 3, limiting its movement, restricting vibration, and reducing deflection, thereby improving the motion accuracy of the grinding wheel 3 and ensuring grinding accuracy. A positioning mechanism is used to position the support sleeve 4, preventing it from moving or rotating axially in a disorderly manner. The support sleeve 4 is a sleeve structure with smooth inner and outer walls. The inner diameter of the support sleeve 4 matches the diameter of the connecting rod 1, and the outer diameter matches the diameter of the ground blind hole. The support sleeve 4 has a certain length, providing a longer support length for the connecting rod 1. Furthermore, the support sleeve 4 extends into the blind hole, reducing the cantilever length of the connecting rod 1 outside the support sleeve 4 and improving the support effect.

[0028] The positioning mechanism can be a positioning component fixed on the worktable 100, and the support sleeve 4 remains in a fixed position. During the axial feeding of the connecting rod 1, in order to ensure that the support sleeve 4 can always provide stable support for the connecting rod 1, the positioning mechanism includes a slide 5, which slides in cooperation with the worktable 100, and the slide 5 is connected to a drive mechanism; a positioning sleeve 6 is provided on the slide 5, and the support sleeve 4 is located inside the positioning sleeve 6 and fixedly connected to the positioning sleeve 6.

[0029] The drive mechanism can move the slide 5, and the direction of movement of the slide 5 is consistent with the axis of the main shaft. As the connecting rod 1 gradually enters the blind hole, the drive mechanism pushes the support sleeve 4 to gradually enter the blind hole as well, avoiding an increase in the cantilever length of the connecting rod 1 extending out of the support sleeve 4, which would lead to an increase in the deflection of the connecting rod 1. The drive mechanism is a hydraulic cylinder 7, but existing facilities such as pneumatic cylinders and linear motors can also be used. The moving speed of the support sleeve 4 can be the same as or different from the feed speed of the connecting rod 1.

[0030] During grinding, a large amount of heat is generated on the surface of the grinding wheel 3, causing the temperature of the grinding wheel 3 to rise. At the same time, grinding produces grinding debris. In order to promote heat dissipation of the grinding wheel 3 and clean the grinding debris on the surface of the grinding wheel 3, this utility model provides a cooling medium inlet channel 8 in the connecting rod 1. The cooling medium inlet channel 8 is coaxial with the connecting rod 1. The connecting rod 1 is provided with an inlet 9 at one end of the connector 2, which is connected to the cooling medium inlet channel 8. The connecting rod 1 is provided with an outlet 10 at one end face of the grinding wheel 3, which is connected to the cooling medium inlet channel 8. The outer wall of the grinding wheel 3 is provided with a cooling groove 11 that penetrates the grinding wheel 3 axially, and the support sleeve 4 is provided with a cooling medium discharge channel 12.

[0031] The cooling medium is typically a coolant, which is pumped into inlet 9 and then flows along cooling medium passage 8 to the grinding end of connecting rod 1. It is then discharged from outlet 10 into a blind hole, flows into cooling tank 11 to cool grinding wheel 3, then flows to support sleeve 4, and finally exits along cooling medium discharge passage 12. During the coolant flow, it not only removes heat from the surface of grinding wheel 3 but also carries away the generated grinding debris.

[0032] The cooling medium discharge channel 12 can be located on the inner wall, outer wall, or entirely inside the support sleeve 4, as long as it can discharge the cooling medium from the blind hole. Because the support sleeve 4 and connecting rod 1 have a clearance fit, the connecting rod 1 rotates at high speed during grinding, while the support sleeve 4 does not rotate. Therefore, it is necessary to avoid excessive friction between the connecting rod 1 and the support sleeve 4. The cooling medium carries grinding debris, some of which has a small particle size. These small grinding debris particles may enter the clearance between the connecting rod 1 and the support sleeve 4, increasing the friction between them and exacerbating the wear of both.

[0033] To prevent wear debris from entering between the connecting rod 1 and the support sleeve 4, a third sealing structure 127 is provided on the inner wall of the end of the support sleeve 4 facing the grinding wheel 3. The third sealing structure 127 serves to seal and prevent wear debris from entering between the connecting rod 1 and the support sleeve 4.

[0034] Conventional machining coolant usually has a lubricating effect. If the coolant can be introduced into the gap between connecting rod 1 and support sleeve 4, the friction between connecting rod 1 and support sleeve 4 can be reduced, the service life of connecting rod 1 and support sleeve 4 can be extended, and the contact surface between connecting rod 1 and support sleeve 4 can be cooled.

[0035] To achieve the above functions, the cooling medium discharge channel 12 includes a first groove 121, a second groove 122, and a discharge port 123. The first groove 121 is located on the outer wall of the support sleeve 4 facing the grinding wheel 3. The first groove 121 extends axially from the end face of the support sleeve 4 for a certain distance. The bottom wall of the first groove 121 is provided with multiple filter holes, which can filter the coolant, allowing it to pass through while preventing grinding debris from passing through. The second groove 122 is located on the inner wall of the support sleeve 4. The second groove 122 can extend axially, be spiral, or be partially a straight groove extending axially and partially spiral. There is a gap between the two ends of the second groove 122 and the end of the support sleeve 4, meaning that neither end of the second groove 122 extends to the end face of the support sleeve 4. One end of the second groove 122 is connected to a filter hole, allowing the filtered coolant to enter. The other end of the second groove 122 is connected to a drain port 123, whose axial direction is aligned with the radial direction of the support sleeve 4. The drain port 123 is located at the end of the support sleeve 4 facing the connector 2. A first sealing structure 125 is provided on the outer wall of the support sleeve 4 between the drain port 123 and the first groove 121. During grinding, the first sealing structure 125 is always located within the blind hole. A second sealing structure 126 is provided on the inner wall of the end of the support sleeve 4 away from the grinding wheel 3. The second groove 122 is located between the second sealing structure 126 and the third sealing structure 127. The first sealing structure 125 prevents coolant from entering the mating gap between the support sleeve 4 and the blind hole wall. The second sealing structure 126 prevents coolant between the connecting rod 1 and the support sleeve 4 from being discharged from the mating gap at the port. The first sealing structure 125, the second sealing structure 126, and the third sealing structure 127 can be achieved using existing technology. A pressure reducing valve 124 is installed inside the outlet 123, which ensures that the coolant discharged from the outlet 123 is always at a constant pressure. The water pressure at the inlet 9 is higher than the outlet water pressure of the pressure reducing valve 124, which promotes the rapid flow of coolant.

[0036] The coolant inside the blind hole carries grinding debris and first enters the first tank 121. The coolant then enters the second tank 122 through the filter holes at the bottom of the first tank 121, while the grinding debris remains in the first tank 121, which serves to store the grinding debris. After grinding, the support sleeve 4 can be removed from the blind hole, and the grinding debris in the first tank 121 can be cleaned. After the coolant enters the second tank 122, since the second tank 122 is located on the inner wall of the support sleeve 4, the support sleeve 4 connects the fitting gap between the support sleeve 4 and the connecting rod 1. The drainage pressure can be controlled by the pressure reducing valve 124, so that the coolant in the second tank 122 has appropriate high pressure. Under the action of high pressure, the coolant in the second tank 122 can fill the fitting gap between the support sleeve 4 and the connecting rod 1, which plays a role in lubrication and cooling, reducing the wear of the support sleeve 4 and the connecting rod 1, and at the same time carrying away the heat generated by friction.

[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A deep blind hole grinding machine, comprising a worktable (100), wherein a slide mechanism (130) and a positioning fixture (120) are provided on the worktable (100), a spindle mechanism (110) is provided on the slide mechanism (130), and a grinding tool is connected to the spindle mechanism (110), characterized in that: The grinding tool includes a connecting rod (1), one end of which is connected to the spindle mechanism (110) via a connector (2), and the outer wall of the other end of the connecting rod (1) is fitted with a grinding tool (3). A support sleeve (4) is fitted over the connecting rod (1) between the connector (2) and the grinding tool (3). The support sleeve (4) is clearance-fitted with the connecting rod (1), and a positioning mechanism is connected to the end of the support sleeve (4) facing the connector (2).

2. The deep blind hole grinding machine as described in claim 1, characterized in that: The positioning mechanism includes a slide (5), which slides in cooperation with the worktable (100), and the slide (5) is connected to a driving mechanism; a positioning sleeve (6) is provided on the slide (5), and the support sleeve (4) is located inside the positioning sleeve (6) and is fixedly connected to the positioning sleeve (6).

3. The deep blind hole grinding machine as described in claim 2, characterized in that: The driving mechanism is a hydraulic cylinder (7).

4. The deep blind hole grinding machine as described in claim 1, characterized in that: The connecting rod (1) is provided with a cooling medium inlet channel (8), and the connecting rod (1) is provided with an inlet (9) at one end of the connector (2). The inlet (9) is connected to the cooling medium inlet channel (8). The connecting rod (1) is provided with an outlet (10) at one end face of the grinding wheel (3). The outlet (10) is connected to the cooling medium inlet channel (8). The outer wall of the grinding wheel (3) is provided with a cooling groove (11) that penetrates the grinding wheel (3) axially. The support sleeve (4) is provided with a cooling medium outlet channel (12).

5. The deep blind hole grinding machine as described in claim 4, characterized in that: The inner wall of the support sleeve (4) facing the mold (3) is provided with a third sealing structure (127).

6. The deep blind hole grinding machine as described in claim 5, characterized in that: The cooling medium discharge channel (12) includes a first tank (121), a second tank (122), and a discharge port (123). The first tank (121) is located on the outer wall of the support sleeve (4) facing the mold (3), and the bottom wall of the first tank (121) is provided with multiple filter holes. The second tank (122) is located on the inner wall of the support sleeve (4), and one end of the second tank (122) is connected to the filter holes, and the other end is connected to the discharge port (123). The discharge port (123) 3) The support sleeve (4) is located at the end facing the connector (2); the outer wall of the support sleeve (4) between the outlet (123) and the first groove (121) is provided with a first sealing structure (125), the inner wall of the support sleeve (4) away from the mold (3) is provided with a second sealing structure (126), the second groove (122) is located between the second sealing structure (126) and the third sealing structure (127); a pressure reducing valve (124) is provided in the outlet (123).

7. The deep blind hole grinding machine as described in claim 1, characterized in that: The grinding wheel (3) is connected to the connecting rod (1) by a plurality of screws.

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