Efficiency test fixture for planetary roller screw pair

Abstract

The invention discloses an efficiency test fixture for a planetary roller screw pair, and relates to the technical field of mechanical product performance test.The efficiency test fixture comprises a screw shaft, a screw pair nut is arranged on the screw shaft, a nut clamping device is clamped on the outer side of the screw pair nut, and the nut clamping device is fixedly connected with a motor shaft connecting assembly; the tail end of the lead screw shaft is fixedly connected with the lead screw clamping device, and the lead screw clamping device is fixedly connected with the hydraulic cylinder thrust end adapter. The nut clamping device comprises a left clamping sleeve, the left clamping sleeve and a right clamping sleeve are connected to form a clamping cavity, the end face of the clamping cavity is matched with the end of the lead screw pair nut in an abutting mode, and the inner circumferential wall of the clamping cavity is in clearance fit with the outer circumferential wall of the lead screw pair nut. The clamping device is simple in structure, high in universality and convenient to assemble, and can meet the efficiency test clamping requirements of planetary roller screws of various models only by changing the boundary dimensions of the nut clamping device and the lead screw clamping device.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical product performance testing, and in particular to a fixture for testing the efficiency of a planetary roller screw pair. Background Art

[0002] The planetary roller screw pair is a mechanical transmission device that can convert rotational motion and linear motion into each other. It is often used in linear actuators of mechanical equipment in military fields such as aerospace, weapons and equipment, and in civilian fields such as CNC machine tools and medical equipment.

[0003] The efficiency of a planetary roller screw is a key indicator of its performance parameters. The efficiency of a planetary roller screw is usually between 70% and 90%, which mainly depends on the friction of the thread pair, the size and direction of the load, the speed, and the lubrication. The efficiency of the screw is usually measured by measuring the ratio of input power to output power. The input power can be measured by a torque sensor and a speed sensor, and the output power can be calculated based on the load force and the linear speed sensor. Finally, the efficiency value can be obtained by dividing the output power by the input power.

[0004] When testing efficiency, we should not only pay attention to the efficiency of the screw itself, but also the test platform and its fixture itself have a huge impact on the test results. Therefore, it is of great significance to design a stable and precise fixture.

[0005] At the same time, due to the diverse appearance and structure of planetary roller screw pairs, using a single fixture to test various types and models of planetary roller screws will result in complex fixture structure and inconvenient installation. Summary of the invention

[0006] The purpose of the present invention is to provide a fixture for testing the efficiency of a planetary roller screw pair, so as to solve the problem mentioned in the background technology that a single fixture is used to test various types and models of planetary roller screws, resulting in a complex fixture structure and inconvenient installation.

[0007] The present invention adopts the following technical solution:

[0008] The present invention discloses a fixture for testing the efficiency of a planetary roller screw pair, comprising a screw shaft, a screw pair nut is threadedly connected to the screw shaft, a nut clamping device is clamped on the outer side of the screw pair nut, the nut clamping device is fixedly connected to a motor shaft connecting assembly, the end of the screw shaft is fixedly connected to the screw clamping device, and the screw clamping device is fixedly connected to a hydraulic cylinder thrust end adapter;

[0009] The nut clamping device includes a left clamping sleeve and a right clamping sleeve, and the left clamping sleeve is connected to the right clamping sleeve by a bolt assembly. After the left clamping sleeve and the right clamping sleeve are connected, a clamping cavity for clamping the screw pair nut is formed, and the inner end surface of the clamping cavity is pressed and matched with the end of the screw pair nut, and the inner circumferential wall of the clamping cavity is gap-fitted with the outer circumferential wall of the screw pair nut.

[0010] Furthermore, a docking shaft is provided at one end of the left clamping sleeve away from the right clamping sleeve, and the docking shaft is connected to the motor shaft connecting assembly; the motor shaft connecting assembly includes a locking nut, and the locking nut is threadedly connected to the docking shaft, a connector is tightly clamped between the locking nut and the left clamping sleeve, and the connector is sleeved on the docking shaft, and the connector is fixedly connected to the motor torque end adapter through a bolt assembly.

[0011] Furthermore, a docking cavity is provided at the axial center position of the motor torque end adapter, and a second keyway is provided on the inner wall of the docking cavity; a first keyway is provided on the docking shaft, the docking shaft is inserted into the docking cavity, and the first keyway is matched with the second keyway through a key connection.

[0012] Furthermore, the screw clamping device includes a flange seat, the flange seat is fixedly connected to the hydraulic cylinder thrust end adapter, a butt joint is arranged at the center of the flange seat, and a screw clamping cavity is arranged in the butt joint;

[0013] The right clamping sleeve is provided with a through hole, and the lead screw shaft passes through the through hole of the right clamping sleeve and is embedded and matched with the lead screw clamping cavity.

[0014] Furthermore, an internal threaded hole is provided in the end of the screw of the screw shaft, a locking hole is provided in the docking joint, the locking hole is coaxially arranged with the screw clamping cavity, a screw is provided in the locking hole, and the screw is threadedly connected to the internal threaded hole.

[0015] Furthermore, a first anti-rotation surface is provided at the end of the screw of the screw shaft, and a second anti-rotation surface is provided on the inner side surface of the screw clamping cavity, and the first anti-rotation surface is embedded and matched with the second anti-rotation surface.

[0016] Furthermore, the motor shaft connecting assembly, the nut clamping device, the screw pair nut, the screw shaft, the screw clamping device, and the hydraulic cylinder thrust end adapter are all coaxially mounted.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are:

[0018] The present invention provides a fixture for testing the efficiency of a planetary roller screw pair, which has a simple structure, is easy to manufacture, easy to operate and use, has strong versatility, and can be quickly disassembled and installed during the efficiency test. The fixture only needs to change the external dimensions of the nut clamping device and the screw clamping device to be applicable to common types of planetary roller screw efficiency tests of different types and models, such as standard and reverse types. At the same time, when the fixture is used, there is no need to perform specific structural processing on the test object, thereby avoiding damage and destruction to the test object. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described below in conjunction with the accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the structure of a fixture for testing the efficiency of a planetary roller screw pair according to the present invention;

[0021] Figure 2 A cross-sectional view of a fixture for testing the efficiency of a planetary roller screw pair according to the present invention;

[0022] Figure 3 It is a structural schematic diagram of a nut clamping device used in a fixture for testing the efficiency of a planetary roller screw pair according to the present invention;

[0023] Figure 4 It is a schematic diagram of the structure of the motor torque end adapter used in the planetary roller screw pair efficiency test fixture of the present invention;

[0024] Figure 5 A cross-sectional view of a screw clamping device used in a fixture for testing the efficiency of a planetary roller screw pair according to the present invention;

[0025] Figure 6 It is a right view of the screw clamping device used in the planetary roller screw pair efficiency test fixture of the present invention;

[0026] Figure 7 It is a structural schematic diagram of a screw clamping device used in a fixture for testing the efficiency of a planetary roller screw pair according to the present invention;

[0027] Figure 8 It is a schematic diagram of the structure of the end of the screw shaft in the fixture for testing the efficiency of the planetary roller screw pair according to the present invention;

[0028] Fig. 9 The present invention is a schematic diagram of the structure of the hydraulic cylinder thrust end adapter used in the planetary roller screw pair efficiency test fixture.

[0029] Explanation of the accompanying drawings: 1. Nut clamping device; 1-1. Left clamping sleeve; 1-2. Right clamping sleeve; 1-3. Docking shaft; 1-4. First keyway; 1-5. Clamping cavity; 2. Screw clamping device; 2-1. Flange seat; 2-2. Docking head; 2-3. Screw clamping cavity; 2-4. Locking hole; 2-5. Screw; 2-6. Second anti-rotation surface; 3. Screw pair nut; 4. Screw shaft; 4-1. Internal threaded hole; 4-2. First anti-rotation surface; 5. Motor shaft connecting assembly; 5-1. Connector; 5-2. Locking nut; 5-3. Motor torque end adapter; 5-4. Docking cavity; 5-5. Key; 5-6. Second keyway; 6. Hydraulic cylinder thrust end adapter. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0031] like Figure 1 and Figure 2 As shown, in this embodiment, a fixture for testing the efficiency of a planetary roller screw pair is disclosed, including a screw shaft 4, a screw pair nut 3 is threadedly connected to the screw shaft 4, a nut clamping device 1 is clamped on the outer side of the screw pair nut 3, and the nut clamping device 1 is fixedly connected to the motor shaft connection assembly 5. The end of the screw shaft 4 is fixedly connected to the screw clamping device 2. The screw clamping device 2 is fixedly connected to the hydraulic cylinder thrust end adapter 6. The nut clamping device 1 and the screw clamping device 2 can be designed with various sizes and specifications according to different models of planetary roller screws.

[0032] like Figures 2 to 4 As shown, the nut clamping device 1 includes a left clamping sleeve 1-1 and a right clamping sleeve 1-2, and the left clamping sleeve 1-1 is connected to the right clamping sleeve 1-2 by a bolt assembly. After the left clamping sleeve 1-1 and the right clamping sleeve 1-2 are connected, a clamping cavity 1-5 for clamping the screw nut 3 is formed. The inner end surface of the clamping cavity 1-5 is pressed against the end of the screw nut 3, which increases the static friction during the test and prevents relative movement during operation. At the same time, the inner circumferential wall of the clamping cavity 1-5 and the outer circumferential wall of the screw nut 3 are clearance-fitted, ensuring the integrity of the structure of the screw nut 3. Both the left clamping sleeve 1-1 and the right clamping sleeve 1-2 are provided with positioning steps that match the outer structure of the screw nut 3, which makes the fixture have good concentricity after assembly and ensures the accuracy of the test results.

[0033] The end of the left clamping sleeve 1-1 away from the right clamping sleeve 1-2 is provided with a docking shaft 1-3, and the docking shaft 1-3 is connected to the motor shaft connection assembly 5. The motor shaft connection assembly 5 includes a locking nut 5-2, and the locking nut 5-2 is threadedly connected to the docking shaft 1-3. The connector 5-1 is tightly clamped between the locking nut 5-2 and the left clamping sleeve 1-1, and the connector 5-1 is sleeved on the docking shaft 1-3. The connector 5-1 is fixedly connected to the motor torque end adapter 5-3 through a bolt assembly, thereby preventing the axial movement of the nut clamping device 1.

[0034] A docking cavity 5-4 is provided at the axis center of the motor torque end adapter 5-3, and a second keyway 5-6 is provided on the inner wall of the docking cavity 5-4. A first keyway 1-4 is provided on the docking shaft 1-3, and the docking shaft 1-3 is inserted into the docking cavity 5-4, and the first keyway 1-4 and the second keyway 5-6 are connected and matched through a key 5-5 to prevent the docking shaft 1-3 from circumferential rotation. When docking, first put the key 5-5 into the first keyway 1-4 on the docking shaft 1-3, then put the docking shaft 1-3 and the key 5-5 into the docking cavity 5-4 together, and insert the key 5-5 into the second keyway 5-6. The coordinated use of the first keyway 1-4, the second keyway 5-6, and the key 5-5 plays a role in preventing circumferential rotation.

[0035] like Figure 2 and Figures 5 to 8 As shown, the screw clamping device 2 includes a flange seat 2-1, which is fixedly connected to the hydraulic cylinder thrust end adapter 6, and a butt joint 2-2 is provided at the center of the flange seat 2-1, and a screw clamping cavity 2-3 is provided in the butt joint 2-2. The right clamping sleeve 1-2 is provided with a through hole, and the screw shaft 4 passes through the through hole of the right clamping sleeve 1-2 and is embedded in the screw clamping cavity 2-3.

[0036] An internal threaded hole 4-1 is provided in the end of the screw of the screw shaft 4, and a locking hole 2-4 is provided in the docking joint 2-2. The locking hole 2-4 is coaxially arranged with the screw clamping cavity 2-3. A screw 2-5 is provided in the locking hole 2-4. The screw 2-5 is threadedly connected with the internal threaded hole 4-1, thereby axially fixing the screw shaft 4 and the screw clamping device 2 together.

[0037] like Figure 7 and Figure 8 As shown, the end of the screw of the screw shaft 4 is provided with a first anti-rotation surface 4-2, and the inner side surface of the screw clamping cavity 2-3 is provided with a second anti-rotation surface 2-6. The first anti-rotation surface 4-2 and the second anti-rotation surface 2-6 are embedded and matched to prevent the screw shaft 4 from circumferential rotation.

[0038] In this embodiment, the motor shaft connection assembly 5, the nut clamping device 1, the screw pair nut 3, the screw shaft 4, the screw clamping device 2, and the hydraulic cylinder thrust end adapter 6 are all coaxially installed. It should be noted that the hydraulic cylinder thrust end adapter 6 can be replaced with an adapter for an electric cylinder, an exciter, or the like according to different types of experimental bench drive devices.

[0039] like Figures 1 to 9 As shown, the assembly process of the present invention is as follows:

[0040] First, place the screw nut 3 in the left clamping sleeve 1-1 and the right clamping sleeve 1-2, and the screw shaft 4 passes through the through hole of the right clamping sleeve 1-2, and the screw nut 3 is wrapped by the left clamping sleeve 1-1 and the right clamping sleeve 1-2. The left clamping sleeve 1-1 and the right clamping sleeve 1-2 are fixed together with screws. When tightening the screws, they need to be tightened gradually in the diagonal direction to prevent the screw nut 3 from slipping between the fixture during the test.

[0041] Then, insert the connector 5-1 and the locking nut 5-2 into the docking shaft 1-3 in sequence, and tighten the locking nut 5-2 on the docking shaft 1-3. Insert the docking shaft 1-3 into the docking cavity 5-4, and ensure that the first keyway 1-4, the second keyway 5-6, and the key 5-5 are key-connected. Then, the connector 5-1 and the motor torque end adapter 5-3 are fixedly connected by a bolt assembly.

[0042] Then, insert the end of the screw shaft 4 into the screw clamping cavity 2-3 of the docking joint 2-2, so that the first anti-rotation surface 4-2 and the second anti-rotation surface 2-6 are embedded and matched, and then insert the screw 2-5 from the locking hole 2-4 and screw it into the internal threaded hole 4-1 of the screw shaft 4 and tighten it.

[0043] After assembly, carefully observe whether there are signs of shaking between the structures of the device. If there is shaking, readjust the tightening torque of each bolt to ensure that the overall structure is stable and firm. After ensuring that the assembly is in place, install the device as a whole on the experimental bench, and the motor torque end adapter 5-3 rotates axially, and the hydraulic cylinder thrust end adapter 6 translates left and right. Before officially starting the test, it is necessary to ensure the runout of the entire detection fixture to determine the overall coaxial condition. You can use a micrometer to rely on the outer cylindrical surface of the left clamping sleeve 1-1 or the right clamping sleeve 1-2, manually rotate the nut clamping device 1, and observe whether the runout of the micrometer is within the test standard range.

[0044] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A fixture for testing the efficiency of a planetary roller screw pair, comprising a screw shaft (4), a screw pair nut (3) being threadedly connected to the screw shaft (4), characterized in that: The outer side of the lead screw pair nut (3) is clamped with a nut clamping device (1), the nut clamping device (1) is fixedly connected to the motor shaft connection assembly (5), the end of the lead screw shaft (4) is fixedly connected to the lead screw clamping device (2), and the lead screw clamping device (2) is fixedly connected to the hydraulic cylinder thrust end adapter (6); The nut clamping device (1) comprises a left clamping sleeve (1-1) and a right clamping sleeve (1-2); the left clamping sleeve (1-1) and the right clamping sleeve (1-2) are connected via a bolt assembly; after the left clamping sleeve (1-1) and the right clamping sleeve (1-2) are connected, a clamping cavity (1-5) for clamping the screw nut (3) is formed; the inner end surface of the clamping cavity (1-5) is pressed against the end of the screw nut (3); and the inner peripheral wall of the clamping cavity (1-5) and the outer peripheral wall of the screw nut (3) are clearance-fitted.

2. The fixture for testing the efficiency of a planetary roller screw pair according to claim 1, characterized in that: A docking shaft (1-3) is provided at one end of the left clamping sleeve (1-1) away from the right clamping sleeve (1-2), and the docking shaft (1-3) is connected to the motor shaft connection assembly (5); The motor shaft connection assembly (5) comprises a locking nut (5-2), the locking nut (5-2) is threadedly connected to the docking shaft (1-3), a connector (5-1) is tightly clamped between the locking nut (5-2) and the left clamping sleeve (1-1), and the connector (5-1) is sleeved on the docking shaft (1-3), and the connector (5-1) is fixedly connected to the motor torque end adapter (5-3) through a bolt assembly.

3. The fixture for testing the efficiency of a planetary roller screw pair according to claim 2, characterized in that: A docking cavity (5-4) is provided at the axial center of the motor torque end adapter (5-3), and a second keyway (5-6) is provided on the inner wall of the docking cavity (5-4); The docking shaft (1-3) is provided with a first keyway (1-4), the docking shaft (1-3) is inserted into the docking cavity (5-4), and the first keyway (1-4) and the second keyway (5-6) are connected and matched via a key (5-5).

4. The fixture for testing the efficiency of a planetary roller screw pair according to claim 1, characterized in that: The screw clamping device (2) comprises a flange seat (2-1), the flange seat (2-1) is fixedly connected to the hydraulic cylinder thrust end adapter (6), a butt joint (2-2) is arranged at the center of the flange seat (2-1), and a screw clamping cavity (2-3) is arranged in the butt joint (2-2); The right clamping sleeve (1-2) is provided with a through hole, and the lead screw shaft (4) passes through the through hole of the right clamping sleeve (1-2) and is embedded and matched with the lead screw clamping cavity (2-3).

5. The fixture for testing the efficiency of a planetary roller screw pair according to claim 4, characterized in that: An internal threaded hole (4-1) is provided in the end of the screw of the screw shaft (4), a locking hole (2-4) is provided in the docking joint (2-2), the locking hole (2-4) is coaxially arranged with the screw clamping cavity (2-3), a screw (2-5) is provided in the locking hole (2-4), and the screw (2-5) is threadedly connected with the internal threaded hole (4-1).

6. The fixture for testing the efficiency of a planetary roller screw pair according to claim 4, characterized in that: The end of the screw of the screw shaft (4) is provided with a first anti-rotation surface (4-2), the inner side surface of the screw clamping cavity (2-3) is provided with a second anti-rotation surface (2-6), and the first anti-rotation surface (4-2) and the second anti-rotation surface (2-6) are embedded and matched.

7. The fixture for testing the efficiency of a planetary roller screw pair according to claim 1, characterized in that: The motor shaft connection assembly (5), the nut clamping device (1), the screw pair nut (3), the screw shaft (4), the screw clamping device (2), and the hydraulic cylinder thrust end adapter (6) are all coaxially mounted.

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