Pre-tensioning structure for transverse feeding ball screw of grinding machine

Abstract

The utility model discloses a grinding machine transverse feed ball screw pre-tensioning structure which comprises a screw rod installed on a bearing seat I and a bearing seat II through a bearing assembly I and a bearing assembly II, the bearing assembly II comprises a pair of angular contact ball bearings which are installed on the screw rod and located in a bearing hole II, and the opposite angles of the angular contact ball bearings are in contact. An inner ring and an outer ring of an angular contact ball bearing are limited in a shaft step of the lead screw and a hole step of a bearing hole II respectively, a locking nut II screwed on the lead screw limits the inner ring of the other angular contact ball bearing, and a gland installed on a bearing seat II limits the outer ring of the angular contact ball bearing. The first bearing assembly comprises a deep groove ball bearing and a thrust bearing which are installed on the lead screw and located in a first bearing hole, an inner ring of the deep groove ball bearing is limited to a shaft step of the lead screw, a gasket is arranged between the thrust bearing and the deep groove ball bearing, the gasket is limited to a hole step of the first bearing hole, and the thrust bearing is pressed on the gasket through a first locking nut screwed on the lead screw. And an interval of 2mm is reserved between the gasket and the end face of the deep groove ball bearing.

Description

Technical Field

[0001] The utility model relates to a grinding machine component, in particular to a grinding machine transverse feed ball screw pre-tensioning structure. Background Art

[0002] Grinding machine is one of the most widely used machine tools. It is widely used in various fields of industrial production, such as molds, tools, automobiles, bearings, machinery manufacturing and other industries.

[0003] The lateral feed mechanism composed of the ball screw nut pair is a key component of the grinder. The ball screw will expand due to frictional heat when working for a long time, thereby increasing the pitch and affecting the operation and positioning accuracy.

[0004] Therefore, when using ball screws in situations where high positioning accuracy is required, the thermal expansion coefficient is usually compensated. Pre-stretching is a relatively common way to compensate for the thermal expansion of the screw during installation. Utility Model Content

[0005] The utility model proposes a pre-tensioning structure for the lateral feed ball screw of a grinding machine, the purpose of which is to solve the problem that the ball screw expands due to frictional heat generated during long-term operation, thereby increasing the pitch and affecting the operation and positioning accuracy, meet high-precision requirements, enhance the rigidity, service life, and load-bearing capacity of the screw, eliminate axial clearance, and thus improve the rigidity and accuracy of the feed system.

[0006] The grinding machine transverse feed ball screw pre-tensioning structure capable of solving the above technical problems comprises a screw rod respectively installed on the bearing seat I and the bearing seat II through the bearing assembly I and the bearing assembly II, the difference being:

[0007] 1. The bearing assembly II comprises a pair of angular contact ball bearings which are installed on the screw and are located in the bearing hole II of the bearing seat II and are in contact with each other diagonally. The inner and outer rings of one angular contact ball bearing are respectively limited to the shaft step of the screw and the bottom of the bearing hole II. The locking nut II screwed on the screw limits the inner ring of the other angular contact ball bearing. The pressure cover installed on the bearing seat II limits the outer ring of the angular contact ball bearing.

[0008] 2. The bearing assembly I comprises a deep groove ball bearing and a thrust bearing which are installed on the screw and located in the bearing hole I of the bearing seat I. The inner ring of the deep groove ball bearing is limited to the shaft step of the screw. A washer is provided between the thrust bearing and the deep groove ball bearing. The washer is limited to the hole step of the stepped bearing hole I. The locking nut I screwed on the screw presses the thrust bearing against the washer to realize the pre-tensioning of the screw. At this time, a gap of 2 mm is retained between the washer and the end face of the deep groove ball bearing.

[0009] Conventionally, a ball nut is screwed onto the screw rod.

[0010] Beneficial effects of the utility model:

[0011] 1. The pre-tensioning structure of the lateral feed ball screw of the grinder of the utility model enhances the rigidity of the screw: the long screw may bend and deform due to its own weight and force, and the pre-tensioning can reduce the possibility of such deformation, thereby ensuring the accuracy of operation.

[0012] 2. The utility model improves the precision of the screw rod: the screw rod may be deformed due to torque and load during use, resulting in reduced precision. Pre-tensioning can reduce the residual deformation of the screw rod and avoid the occurrence of precision errors.

[0013] 3. The utility model prolongs the service life of the screw rod: pre-stretching can improve the rigidity and precision of the screw rod, effectively reduce the deformation of the screw rod during work, and thus increase the service life of the screw rod.

[0014] 4. The utility model improves the rigidity and stability of the ball screw: pre-stretching can keep the ball screw in a certain tension state, prevent excessive deformation and vibration, and ensure its load-bearing capacity and service life.

[0015] 5. The utility model eliminates the axial clearance, improves the rigidity of the ball screw, reduces the elastic deformation of the ball body, the screw rod and the nut, and improves the rigidity and precision of the feed system.

[0016] 6. The utility model greatly improves the feed sensitivity and positioning accuracy of the feed mechanism, which can reach 0.005mm. Generally, pre-tensioning is not adopted, and the feed sensitivity and positioning accuracy are 0.02mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of an implementation method of the utility model.

[0018] Figure 2 for Figure 1 A partial enlarged view of point A in the middle.

[0019] Figure number identification: 1. Screw; 2. Ball nut; 3. Bearing seat I; 4. Bearing seat II; 5. Deep groove ball bearing; 6. Thrust bearing; 7. Washer; 8. Angular contact ball bearing; 9. Locking nut I; 10. Pressure cover; 11. Locking nut II. DETAILED DESCRIPTION

[0020] The technical solution of the utility model is further described below in conjunction with the implementation modes shown in the accompanying drawings.

[0021] The utility model grinder transverse feed ball screw pre-tensioning structure comprises a screw rod 1, a ball nut 2 is screwed on the screw rod 1, the left part of the screw rod 1 is installed in the bearing hole Ⅰ of the bearing seat Ⅰ3 through the bearing assembly Ⅰ to achieve left end support, and the right part of the screw rod 1 is installed in the bearing hole Ⅱ of the bearing seat Ⅱ4 through the bearing assembly Ⅱ to achieve right end support. Figure 1 shown.

[0022] The bearing assembly II includes a pair of angular contact ball bearings 8 that are diagonally in contact with each other and are mounted on the screw 1. The inner ring of the left angular contact ball bearing 8 is limited to the shaft step on the screw 1, and the outer ring of the left angular contact ball bearing 8 is limited to the bottom of the bearing hole II. A locking nut II 11 is screwed on the screw 1. The locking nut II 11 is screwed to the left to limit the inner ring of the right angular contact ball bearing 8. A pressure cover 10 is installed on the right end surface of the bearing seat II 4 with screws. The lip of the pressure cover 10 enters the bearing hole II to limit the outer ring of the right angular contact ball bearing 8. Figure 1 shown.

[0023] The bearing assembly I comprises a thrust bearing 6 on the left side and a deep groove ball bearing 5 on the right side mounted on the screw rod 1. The right end of the inner ring of the deep groove ball bearing 5 is limited to the shaft step on the screw rod 1. A washer 7 sleeved on the screw rod 1 is provided between the thrust bearing 6 and the deep groove ball bearing 5. The right end face of the washer 7 is limited to the hole step of the stepped bearing hole I. A locking nut I9 is ​​screwed on the screw rod 1. The locking nut I9 is ​​screwed to the right to press the thrust bearing 6 to the right and the position is limited by the washer 7. A gap of 2 mm is retained between the washer 7 and the deep groove ball bearing 5. Figure 1 , Figure 2 shown.

[0024] The steps of the pre-tensioning scheme of the utility model are:

[0025] 1. The left and right ends of the screw rod 1 are installed in place in the bearing holes of the bearing seat Ⅰ3 and the bearing seat Ⅱ4 through the bearing assembly Ⅰ and the bearing assembly Ⅱ. The positive generatrix and the side generatrix of the ball screw are checked in turn to make the parallelism of the positive generatrix, the side generatrix and the relevant reference surface meet the requirements.

[0026] 2. Remove the locking nut I9, thrust bearing 6 and washer 7, and replace the original washer 7 with a washer 7 with a reduced thickness. The amount of thinning of the washer 7 is equal to the pre-stretching amount of the screw rod 1.

[0027] 3. Reinstall the thinned washer 7, thrust bearing 6 and locking nut I9, and tighten the locking nut I9 to pre-stretch the screw rod 1.

[0028] 4. At the pre-stretched position of the screw rod 1, the interval between the thinned washer 7 and the deep groove ball bearing 5 is 2 mm.

[0029] Through the pre-tensioning scheme of the utility model, the ball screw is pre-stretched to a certain length so that it can reach the axial force required in the working state. When the working load acts on the screw rod 1, the screw rod 1 will not undergo axial deformation or displacement, thereby ensuring the stability and safety of the structure. The pre-tightening force is added through pre-stretching to eliminate the axial clearance, increase the rigidity of the screw rod 1, reduce the elastic deformation between the screw rod 1 and the ball nut 2, and improve the rigidity and accuracy of the feed system.

[0030] The utility model has a reasonable structure and can effectively enhance the rigidity of the screw rod 1 and reduce the residual deformation of the screw rod 1 through pre-tensioning, avoid the generation of precision errors, extend the service life of the screw rod, improve the rigidity and stability of the ball screw, ensure its load-bearing capacity and working life, eliminate axial clearance, and thus improve the rigidity and precision of the feed system.

Claims

1. A grinding machine transverse feed ball screw pre-tensioning structure, comprising a screw (1) mounted on a bearing seat I (3) and a bearing seat II (4) through a bearing assembly I and a bearing assembly II, respectively, and characterized in that: The bearing assembly II comprises a pair of angular contact ball bearings (8) which are installed on the screw (1) and are located in the bearing hole II of the bearing seat II (4), and are in contact with each other diagonally. The inner and outer rings of one angular contact ball bearing (8) are respectively limited to the shaft step of the screw (1) and the bottom of the bearing hole. A locking nut II (11) screwed on the screw (1) limits the inner ring of the other angular contact ball bearing (8). A pressure cover (10) installed on the bearing seat II (4) limits the outer ring of the angular contact ball bearing (8). The bearing assembly I comprises a deep groove ball bearing (5) and a thrust bearing (6) which are installed on the screw (1) and are located in the bearing hole I of the bearing seat I (3). The inner ring of the deep groove ball bearing (5) is limited to the axial step of the screw (1). A washer (7) is provided between the thrust bearing (6) and the deep groove ball bearing (5). The washer (7) is limited to the hole step of the stepped bearing hole I. The locking nut I (9) screwed on the screw (1) presses the thrust bearing (6) against the washer (7) to achieve pre-tensioning of the screw (1). At this time, a 2 mm gap is retained between the washer (7) and the end face of the deep groove ball bearing (5).

2. The grinding machine transverse feed ball screw pre-tensioning structure according to claim 1, characterized in that: A ball nut (2) is screwed onto the screw rod (1).

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