A half-enclosed ball screw with a spline

Abstract

This invention relates to a semi-enclosed ball screw with an integrated spline, comprising: a cylindrical housing; a drive assembly disposed within the cylindrical housing; a ball nut disposed on the cylindrical housing and screwed to the drive assembly; a ball spline groove disposed on one side of the cylindrical housing; and a spline groove disposed within the ball nut and mating with the ball spline groove, wherein a plurality of balls are disposed within the spline groove, the balls reducing the friction between the spline groove and the ball spline groove. This invention requires only one motor to achieve the reciprocating motion of the ball screw. A motor is installed on the right side of the ball screw to drive the ball screw in both forward and reverse directions, allowing the ball nut to reciprocate on the screw. A cylindrical housing is installed on the outside of the ball screw, with a ball spline groove formed on the cylindrical housing. A spline groove is installed on the ball nut, mating with the ball spline groove, so that the ball nut can only move along the direction of the ball spline groove during forward and backward movement.

Description

Technical Field

[0001] This invention relates to the field of transmission device technology, specifically to a semi-enclosed ball screw with integrated splines. Background Technology

[0002] Ball screws are ideal products for converting rotary motion into linear motion, or vice versa. They are the most commonly used transmission components in machine tools and precision machinery. Their main function is to convert rotary motion into linear motion, or torque into axial reciprocating force, while also possessing high precision, reversibility, and high efficiency. Due to their very low frictional resistance, ball screws are widely used in various industrial equipment and precision instruments.

[0003] However, existing ball screws with spline grooves are inconvenient to lubricate, and the spline and ball nut are separate rather than integrated, resulting in a complex structure and low working efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a semi-enclosed ball screw with integrated spline to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a semi-enclosed ball screw with integrated spline, comprising:

[0006] Cylindrical shell;

[0007] The drive assembly is located inside the cylindrical housing;

[0008] A ball nut is disposed on the cylindrical housing and screwed to the drive assembly;

[0009] A ball spline groove is provided on one side of the cylindrical housing;

[0010] A spline groove is provided inside the ball nut and fits into the ball spline groove. The spline groove is provided with a plurality of balls, which can reduce the friction between the spline groove and the ball spline groove.

[0011] As an optional embodiment of the present invention, the driving component may optionally include:

[0012] The bearing is located inside the cylindrical housing;

[0013] A ball screw is disposed inside the cylindrical housing and connected to the bearing, wherein the bearing and the ball screw are arranged concentrically.

[0014] As an optional embodiment of the present invention, the cylindrical housing is provided with the bearings at both ends, and the two ends of the ball screw are respectively provided on the two bearings.

[0015] As an optional embodiment of the present invention, the cylindrical housing is provided with an opening in the axial direction, and the ball nut is also provided with a plurality of arc-shaped protrusions. The arc-shaped protrusions can be tightly engaged with the threads on the ball screw through the opening. A plurality of steel balls are provided at the contact surfaces of all the arc-shaped protrusions and the ball screw to reduce the friction between the arc-shaped protrusions and the ball screw.

[0016] As an optional embodiment of the present invention, the top of the thread is a plane, and an oil groove is provided at the center of the thread, the oil groove being arranged along the thread direction.

[0017] As an optional embodiment of the present invention, optionally, the top of the opening at both ends of the cylindrical housing is provided with a stop block, and the two stop blocks are respectively provided with folded cloth. One end of the two folded cloths is connected to the two stop blocks, and the other end is connected to the left and right sides of the ball nut.

[0018] As an optional embodiment of the present invention, the two sides of the folded fabric are provided with sliding grooves on the cylindrical shell, and the two sides of the folded fabric can be movably connected to the sliding grooves by means of ball joints.

[0019] As an optional embodiment of the present invention, the folded fabric may be laid along the opening to completely cover the opening.

[0020] As an optional embodiment of the present invention, the lengths of the folded fabrics on the left and right sides of the ball nut are equal, and the lengths of the two folded fabrics are greater than or equal to the length of the opening.

[0021] As an optional embodiment of the present invention, the length of the arcuate protrusion is optionally less than the width of the opening.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention only requires one motor to realize the reciprocating motion of the ball screw. The motor is installed on the right side of the ball screw to drive the ball screw to rotate forward and backward, so that the ball nut can reciprocate on the screw. A cylindrical housing is installed on the outside of the ball screw, and a ball spline groove is opened on the cylindrical housing. A spline groove is installed on the ball nut. The spline groove fits into the ball spline groove, so that when the ball nut moves back and forth, it can only move along the direction of the ball spline groove. An oil groove is opened on the thread of the ball screw. When grease is applied to the ball screw, the oil groove will contain and store grease. During the rotation of the ball screw, the centrifugal force will throw the grease in the oil groove little by little, which plays a role in lubricating the ball screw 2. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the present invention;

[0025] Figure 3 This is a partial structural schematic diagram of the present invention;

[0026] Figure 4 This is a partial structural schematic diagram of the present invention.

[0027] In the diagram: 1. Cylindrical housing; 2. Ball screw; 3. Ball nut; 4. Bearing; 5. Ball spline groove; 6. Opening; 7. Stop; 8. Folded cloth; 9. Thread; 10. Oil groove; 11. Arc-shaped protrusion; 12. Spline groove. Detailed Implementation

[0028] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0029] like Figures 1 to 4 As shown, a semi-enclosed ball screw with integrated spline includes:

[0030] Cylindrical housing 1; Cylindrical housing 1 serves two purposes: firstly, to protect the ball screw 2 from dust entering and affecting its accuracy; secondly, to serve as the movement track for the ball nut 3; Cylindrical housing 1 is made of metal material, preferably stainless steel.

[0031] A drive assembly is disposed within the cylindrical housing 1; the drive assembly includes the bearing 4 and the ball screw 2, and a motor is installed on one side of the ball screw 2 to drive the ball screw 2 to rotate.

[0032] A ball nut 3 is disposed on the cylindrical housing 1 and screwed to the drive assembly; the inner wall of the ball nut 3 is provided with an arc-shaped protrusion 11, which is screwed to the thread 9 on the ball screw 2. When the ball screw 2 rotates under the drive of the motor, the ball nut 3 will reciprocate on the cylindrical housing 1; the inner diameter of the ball nut 3 is slightly larger than the outer diameter of the cylindrical housing 1.

[0033] A ball spline groove 5 is provided on one side of the cylindrical housing 1; the ball spline groove 5 is provided on both the front and rear sides of the ball spline groove 5, which is used to cooperate with the spline groove 12 on the ball nut 3 so that the ball nut 3 does not swing left and right when moving.

[0034] Spline groove 12 is located within the ball nut 3 and fits into the ball spline groove 5. A plurality of balls are provided within the spline groove 12, which reduces the friction between the spline groove 12 and the ball spline groove 5. Spline grooves 12 are respectively provided on the inner side of the spline groove 12 at corresponding positions to the two ball spline grooves 5; each of the two spline grooves 12 is fitted with a ball, and the spline groove 12 contacts the ball spline groove 5 through the internal balls, thus minimizing the friction between the spline groove 12 and the ball spline groove 5.

[0035] like Figure 1 As shown, the cylindrical housing 1 has bearings 4 welded to both ends. The left and right ends of the ball screw 2 are fixed within the inner rings of the two bearings 4, allowing the ball screw 2 to rotate freely within the two bearings 4. The ball screw 2 has threads 9. The cylindrical housing 1 also has an opening 6. Several arc-shaped protrusions 11 in the ball nut 3 pass through the opening 6 and engage with the threads 9 on the ball screw 2. Several steel balls are provided in the arc-shaped protrusions 11. The arc-shaped protrusions 11 contact the threads 9 through the steel balls, which greatly reduces the friction between the arc-shaped protrusions 11 and the threads 9. In use, the motor drives the ball screw 2 to rotate. Since the arc-shaped protrusions 11 in the ball nut 3 are embedded in the threads 9 of the ball screw 2, the ball nut 3 reciprocates linearly under the traction of the two ball spline grooves 5 and the two spline grooves 12.

[0036] As an optional embodiment of the present invention, the driving component may optionally include:

[0037] Bearing 4 is disposed inside the cylindrical housing 1; the outer diameter of the two bearings 4 is equal to the inner diameter of the cylindrical housing 1, and the two bearings 4 are respectively welded to both ends inside the cylindrical housing 1.

[0038] A ball screw 2 is disposed within the cylindrical housing 1 and connected to the bearing 4, which is concentrically arranged with the ball screw 2. Both ends of the ball screw 2 are welded to the two bearings 4 respectively, and one end of the ball screw 2 is connected to a motor, servo motor, or stepper motor.

[0039] like Figure 1 As shown, during use, the ball screw 2 rotates within the cylindrical housing 1 under the traction of the motor, with the two bearings 4 as fulcrums.

[0040] As an optional embodiment of the present invention, the cylindrical housing 1 is provided with the bearing 4 at both ends, and the two ends of the ball screw 2 are respectively provided on the two bearings 4.

[0041] like Figure 1 As shown, the diameter of the ball screw 2 is slightly smaller than the diameter of the inner ring of the bearing 4, and the ball screw 2 can pass smoothly through the bearing 4.

[0042] As an optional embodiment of the present invention, the cylindrical housing 1 is provided with an opening 6 in the axial direction, and the ball nut 3 is also provided with a plurality of arc-shaped protrusions 11. The arc-shaped protrusions 11 can be tightly engaged with the threads 9 on the ball screw 2 through the opening 6. A plurality of steel balls are provided at the contact surface between the arc-shaped protrusions 11 and the ball screw 2, which can reduce the friction between the arc-shaped protrusions 11 and the ball screw 2.

[0043] like Figure 1 As shown in Figure 4, the width of the opening 6 is greater than the length of the arc-shaped protrusion 11. When the ball nut 3 moves, the opening 6 will not affect the forward and backward movement of the arc-shaped protrusion 11. Each arc-shaped protrusion 11 is provided with several steel balls. The arc-shaped protrusion 11 contacts the ball screw 2 through the steel balls, which can greatly reduce the friction between the arc-shaped protrusion 11 and the ball screw 2.

[0044] As an optional embodiment of the present invention, the top of the thread 9 is a plane, and an oil groove 10 is provided at the center of the thread 9, the oil groove 10 being arranged along the direction of the thread 9.

[0045] like Figure 3 As shown, the oil groove 10 on the thread 9 is used to store grease. When the ball screw 2 rotates, the centrifugal force will throw the grease in the oil groove 10 out little by little, which will lubricate the ball screw 2.

[0046] As an optional embodiment of the present invention, optionally, the top of the opening 6 on the cylindrical housing 1 is provided with a stop block 7 at both ends, and the two stop blocks 7 are respectively provided with a folded cloth 8. One end of the two folded cloths 8 is connected to the two stop blocks 7, and the other end is connected to the left and right sides of the ball nut 3.

[0047] like Figure 3 As shown, the folded cloth 8 is used to cover the opening 6 to prevent dust and impurities from entering the cylindrical housing 1 and affecting accuracy. The two stops 7 are respectively welded to the two ends of the opening 6 on the cylindrical housing 1, and one end of the folded cloth 8 is fixed to the stop 7. In use, when the ball nut 3 moves forward, the folded cloth 8 in front of the ball nut 3 retracts under the pushing force of the ball nut 3, and the folded cloth 8 behind the ball nut 3 extends under the pulling force of the ball nut 3, both completely blocking the opening 6 and preventing dust from entering the cylindrical housing 1.

[0048] As an optional embodiment of the present invention, the two sides of the folded fabric 8 are provided with sliding grooves on the cylindrical housing 1, and the two sides of the folded fabric 8 can be movably connected to the sliding grooves by means of ball clamps.

[0049] like Figure 3 As shown, since the middle part of the folded cloth 8 is prone to slipping during the movement of the folded cloth 8, the groove is also provided on the cylindrical housing 1. The two sides of the folded cloth 8 can be movably connected to the groove by ball bearings to prevent the middle part of the folded cloth 8 from slipping. During the movement of the folded cloth 8, the groove will not generate a large friction force that affects the movement of the ball nut 3. The two ends of the folded cloth 8 can easily slide freely in the groove.

[0050] As an optional embodiment of the present invention, the folded fabric 8 may be laid along the opening 6 to completely cover the opening 6.

[0051] like Figure 3 As shown, the width of the folded fabric 8 is greater than the width of the opening 6; a sliding groove is opened on each of the two sides of the cylindrical shell 1, and the two sides of the folded fabric 8 are locked in the sliding groove by the locking ball. The locking ball is sleeved on the folded fabric 8, so it can completely block the opening 6. The locking ball can move arbitrarily in the locking groove under the pull of the folded fabric 8.

[0052] As an optional embodiment of the present invention, the lengths of the folded cloths 8 on the left and right sides of the ball nut 3 are equal, and the lengths of the two folded cloths 8 are greater than or equal to the length of the opening 6.

[0053] like Figure 3 As shown, the folded cloth 8 is made of EPTEE laminated, PU fabric, TPU fabric, nylon silk and other fabrics; when the ball nut 3 moves to its maximum left and right stroke, the folded cloth 8 is also stretched to its farthest distance. If the length of the folded cloth 8 is less than the length of the opening 6, the ball nut 3 and the folded cloth 8 will generate a large force, which can easily damage the components and cause unnecessary losses. Therefore, the length of the folded cloth 8 can only be greater than or equal to the length of the opening 6.

[0054] As an optional embodiment of the present invention, the length of the arcuate protrusion 11 may be less than the width of the opening 6.

[0055] like Figure 1As shown in Figure 4, when the ball nut 3 moves back and forth, the arc-shaped protrusion 11 fixed inside the ball nut 3 will reciprocate along the direction of the opening 6 within the opening 6 under the drive of the ball screw 2. If the length of the arc-shaped protrusion 11 is greater than the width of the opening 6, a large frictional force will be generated between the arc-shaped protrusion 11 and the opening 6 during movement, which will affect the movement of the ball nut 3 and easily damage the components. Therefore, the length of the arc-shaped protrusion 11 is less than the width of the opening 6 to ensure that the ball nut 3 moves unimpeded.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A semi-enclosed ball screw with integrated spline, characterized in that, include: Cylindrical shell (1); The drive assembly is located inside the cylindrical housing (1); A ball nut (3) is disposed on the cylindrical housing (1) and screwed to the drive assembly; A ball spline groove (5) is provided on one side of the cylindrical housing (1); A spline groove (12) is provided in the ball nut (3) and fits in the ball spline groove (5). A plurality of balls are provided in the spline groove (12), and the balls reduce the friction between the spline groove (12) and the ball spline groove (5). The driving component includes: The bearing (4) is located inside the cylindrical housing (1); A ball screw (2) is disposed inside the cylindrical housing (1) and connected to the bearing (4), wherein the bearing (4) and the ball screw (2) are arranged concentrically; The cylindrical housing (1) has an opening (6) in the axial direction. The ball nut (3) is also provided with several arc-shaped protrusions (11). The arc-shaped protrusions (11) are tightly engaged with the threads (9) on the ball screw (2) through the opening (6). Several steel balls are provided at the contact surfaces of all the arc-shaped protrusions (11) and the ball screw (2) to reduce the friction between the arc-shaped protrusions (11) and the ball screw (2).

2. The semi-enclosed ball screw with integrated spline as described in claim 1, characterized in that, The cylindrical housing (1) is provided with bearings (4) at both ends, and the two ends of the ball screw (2) are respectively provided on the two bearings (4).

3. The semi-enclosed ball screw with integrated spline as described in claim 1, characterized in that, The top of the thread (9) is flat, and an oil groove (10) is provided in the center of the thread (9). The oil groove (10) is arranged along the direction of the thread (9).

4. A semi-enclosed ball screw with integrated spline as described in claim 3, characterized in that, The top of the opening (6) on the cylindrical shell (1) is provided with a stop block (7) at both ends. The two stop blocks (7) are provided with folded cloth (8). One end of the two folded cloths (8) is connected to the two stop blocks (7), and the other end is connected to the left and right sides of the ball nut (3).

5. A semi-enclosed ball screw with integrated spline as described in claim 4, characterized in that, The two sides of the folded cloth (8) are provided with sliding grooves on the cylindrical shell (1), and the two sides of the folded cloth (8) are movably connected to the sliding grooves by means of ball clamps.

6. A semi-enclosed ball screw with integrated spline as described in claim 5, characterized in that, The folded fabric (8) is laid along the opening (6) to completely cover the opening (6).

7. A semi-enclosed ball screw with integrated spline as described in claim 6, characterized in that, The lengths of the folded cloths (8) on the left and right sides of the ball nut (3) are equal, and the lengths of the two folded cloths (8) are greater than or equal to the length of the opening (6).

8. A semi-enclosed ball screw with integrated spline as described in claim 6, characterized in that, The length of the arc-shaped protrusion (11) is less than the width of the opening (6).

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