JPH04124886U - Lead screw type stepping motor - Google Patents

Abstract

(57) [Summary] [Objective] To provide a lead screw type stepping motor with a simple structure and low cost, in which the protruding end of the rotating shaft does not fall off from the pivot bearing. [Structure] In the lead screw type stepping motor of the present invention, the tip of the rotating shaft is rotatably supported via a thrust bearing having a gap in the center, and has a protrusion that engages with the center gap of the thrust bearing. Therefore, even if the rotary shaft moves toward the motor due to impact or load fluctuation, the protruding end of the rotary shaft will not fall off from the pivot bearing.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a lead screw type stepping motor, especially at the tip of the rotating shaft. Lead screw type stepping that is rotatably supported via a pivot bearing Regarding motors.

0002

[Conventional technology]

Generally, one end of the rotating shaft protrudes long from the end face of the stepping motor, and the protruding part A spiral lead screw groove is engraved on the rotation axis of the motor, which moves forward as the motor rotates. A lead that moves the engaging member that engages with the lead screw groove in parallel along the rotation axis. In a double screw type stepping motor, the end of the rotating shaft on the motor side is It is compressed in the axial direction by the compression means provided at the end, and the protruding end of the rotating shaft is It is rotatably supported via a bot bearing and is attached to the end face of the motor on the side where the rotating shaft passes through. is a lead screw equipped with radial bearings that rotatably supports the rotating shaft. Dew-type stepping motors are known.

0003 FIG. 3 shows a conventional lead screw type stepping motor. this lead The screw type stepping motor 31 has a stepping motor 32, and has a stepping motor 32. The rotating shaft 33 of the ping motor 32 protrudes long from the end surface of the stepping motor 32. ing. A spiral lead screw groove 3 is provided on the outer peripheral surface of the protruding portion of the rotating shaft 33. 4 is engraved and engages with the lead screw groove 34 by rotation of the rotating shaft 33. An engaging member (not shown) is translated in parallel along the rotating shaft 33.

0004 The end of the rotating shaft 33 on the motor side is connected to a sprocket attached to the end plate of the stepping motor. A compressive force is applied in the axial direction by the ring piece 35.

[0005] The end of the stepping motor 32 on the side through which the rotating shaft 33 passes is a metal bearing 36. The rotating shaft 33 is rotatably supported.

[0006] The protruding end of the rotating shaft 33 is connected to a pivot bearing 38 via a bracket 37. axial movement is restricted and is rotatably supported.

[0007]

[Problem that the idea aims to solve]

However, with conventional lead screw type stepping motors, shock and Due to load fluctuations in the members that engage with the lead screw, the rotating shaft is rotated in the F direction as shown in the figure. In other words, a force that pushes the rotating shaft toward the motor side acts, and the rotating shaft is attached to the end face of the motor. By pushing back the spring piece that has been removed, the rotating shaft moves toward the motor, and the The tip of the protruding side will be lifted from the pivot bearing. As a result, the protruding side of the rotating shaft There was a problem with the tip falling off the pivot bearing.

[0008] Figure 4 shows that the rotating shaft of the conventional lead screw type stepping motor described above is This figure shows the state in which the protruding end of the rotating shaft has fallen off from the pivot bearing. It is.

[0009] In addition, in order to solve the above problem, we have developed a pivot with a guide to prevent the tip of the rotating shaft from falling off, as shown in Figure 5. A method using a pivot bearing is known, but the structure of the pivot bearing becomes complicated and costs increase. It was high.

0010 Therefore, the purpose of this invention is to provide a simple structure, low cost, and the protruding end of the rotating shaft. A lead screw type stepping motor that will not fall off the pivot bearing. It is about providing.

[0011]

[Means to solve the problem]

In order to solve the above purpose, the lead screw type stepping motor of this invention is , the rotating shaft protrudes long from the end face of the stepping motor, and the rotating shaft of the protruding part A spiral lead screw groove is carved on the outer circumferential surface of the lead screw, and the lead screw is A rib that moves the engaging member that engages with the blade screw groove along the rotation axis. In a door screw type stepping motor, the tip of the rotating shaft has a hole in the center. It is rotatably supported via a pivot bearing with a gap, and a pin is attached to the tip of the rotating shaft. It is characterized by having a protrusion that engages with the central cavity of the bot bearing. .

0012

【Example】

FIG. 1 shows the entire lead screw type stepping motor of the present invention. In Fig. 1, the lead screw type stepping motor 11 is a stepping motor. The rotating shaft 13 of the stepping motor 12 is connected to the stepping motor 1. It protrudes long from the end face of 2. The outer peripheral surface of the protruding part of the rotating shaft 13 has a spiral shape. A lead screw groove 14 is formed, and the lead screw is rotated by rotation of the rotating shaft 13. An engaging member (not shown) that engages with the screw groove 14 is moved in parallel along the rotating shaft 13. . The end of the rotating shaft 13 on the motor side is attached to the end plate of the stepping motor. A compressive force is applied in the axial direction by the pulling piece 15.

[0013] The end of the stepping motor 12 on the side through which the rotating shaft 13 passes is a metal bearing 16. The curved rotating shaft 13 is rotatably supported.

[0014] The protruding end of the rotating shaft 13 is connected to the pivot bearing 18 via the bracket 17. It is rotatably supported while being restricted from moving in the axial direction.

[0015] The protruding end of the rotating shaft 13 engages with the gap 19 at the center of the pivot bearing 18. A projection 20 is provided.

[0016] As mentioned above, the protruding end of the rotating shaft 13 has a hollow space in the center of the pivot bearing 18. Since a protrusion 20 that engages with the gap 19 is provided, it will not engage with the impact and lead screw. Even if the rotating shaft moves toward the motor side due to load fluctuations on the parts being rotated, the protruding end of the rotating shaft will It does not lift up from the pivot bearing, and the protruding end of the rotating shaft is attached to the pivot bearing 18. It will never fall off.

[0017] FIG. 2 shows a detailed explanation of the protruding end of the rotating shaft and the pivot bearing portion of the embodiment shown in FIG. 1. It is something.

[0018] The protruding end of the rotating shaft 23 engages with the gap 29 at the center of the pivot bearing 28. Since the protrusion 24 is provided, even if the rotating shaft moves toward the motor side, the rotating shaft will still remain on the protruding side. The protrusion at the tip engages the gap in the center of the pivot bearing, and the tip on the protruding side of the rotating shaft is attached to the pivot bearing. The protruding end of the rotating shaft does not come off the pivot bearing 28. It won't fall.

[0019]

[Effect of the idea]

As is clear from the above explanation, the lead screw type stepping motor of the present invention The rotary shaft has a protrusion on the protruding end of the rotating shaft that engages with the central cavity of the pivot bearing. Since it is only necessary to provide a Even if the rotating shaft moves toward the motor, the tip of the rotating shaft will fall off from the pivot bearing. A lead screw type stepping motor with a simple structure and low cost. You can get ta.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the lead screw type stepping motor of the present invention in the direction of the rotation axis.

FIG. 2 is a detailed view of the protruding end of the rotating shaft and the pivot bearing of the lead screw type stepping motor of the present invention.

FIG. 3 is a cross-sectional view of a conventional lead screw type stepping motor in the direction of the rotation axis.

FIG. 4 is a diagram showing a state in which the tip of a rotating shaft of a conventional lead screw type stepping motor has fallen off from a pivot bearing.

FIG. 5 is a diagram showing a pivot bearing with a guide to prevent the tip of the rotating shaft from falling off and the rotating shaft.

[Explanation of symbols]

11, 31, 41 Lead screw type stepping motor 12, 32, 42 Stepping motor 13, 23, 33, 43, 53 Rotating shaft 14, 34 Spiral lead screw groove 15, 35, 45 Spring piece 16, 36 Metal bearing 17 , 37, 47 Bracket 18, 28, 38, 48, 58 Pivot bearing 19, 29 Gap in center of pivot bearing 20, 24 Protrusion 59 on the protruding end of the rotating shaft Guide to prevent the tip of the rotating shaft from falling off

Claims (1)

[Scope of utility model registration request] Claim 1: A rotating shaft is made to protrude long from an end face of a stepping motor, a spiral lead screw groove is carved on the outer circumferential surface of the protruding portion of the rotating shaft, and the rotating shaft is engaged with the lead screw groove as the motor rotates. In a lead screw type stepping motor in which an engaging member is moved along a rotating shaft, the tip of the rotating shaft is rotatably supported via a pivot bearing having a gap in the center. A lead screw type stepping motor, characterized in that it has a protrusion that engages with the central gap of the pivot bearing.