JPH0578469U - Shot peening equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] Shots with different grain sizes are sequentially projected by one device to effectively improve the metal strength. [Structure] A plurality of air nozzles 5A, 5B facing a chamber 1 for accommodating and mounting a workpiece 2, a plurality of hoppers 6A, 6B filled with shots having different particle sizes, and a hopper 6
Air lines 9A and 9B for sending pressurized air so that shots A and 6B are ejected from the respective air nozzles 5A and 5B.
And switching valves 8A, 8B for selectively connecting the hoppers 6A, 6B to the air nozzles 5A, 5B and air switching valves 4A, 4B interposed in the air lines 9A, 9B.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a shot peening apparatus that projects a shot (steel ball) onto the surface of a workpiece such as a gear to increase the material strength.

[0002]

[Prior art]

 In order to improve the fatigue strength of metal materials, Japanese Patent Laid-Open No. 2-185369 discloses a device for performing shot peening by gradually increasing or decreasing the shot injection pressure. However, in this case, since the shots of the same grain size are projected, the effect does not improve as expected.

On the other hand, Japanese Patent Application Laid-Open No. 2-185370 proposes to effectively increase the fatigue strength by projecting two kinds of shots having different grain sizes stepwise. According to this, a shot with a large grain size is first projected to exert a compressive residual stress from the surface of the workpiece to a deep point, and then a shot with a small grain size is projected to compress the near-surface of the workpiece. The residual stress is further increased and the rough surface is smoothed by the previous shot with a large grain size.

[0004]

[Problems to be solved by the device]

 However, with this device, it is necessary to prepare separate shot peening devices for shots with different grain sizes, which requires a large installation space, complicates the device, and increases the work process. ..

The present invention aims to solve such problems.

[0006]

[Means for Solving the Problems]

 The present invention has a plurality of air nozzles facing a chamber for storing and placing a work piece, a plurality of hoppers filled with shots having different particle diameters, and a pressurizing shot of each hopper to be ejected from each air nozzle. It is provided with a plurality of air lines for feeding air and a switching valve interposed in each air line so as to selectively project a shot from each air nozzle.

[0007]

[Action]

 Therefore, when performing shot peening processing, first, the shot is projected from the air nozzle connected to the hopper filled with the shot having a large particle diameter, and the switching valve is switched so as to stop the projection of the shot from the other air nozzle. A shot with a large grain size is projected onto a workpiece from an air nozzle via pressurized air. Next, the switching valve is switched to stop the shot with a large particle size and project a shot with a small particle size.

In this way, one shot peening apparatus can selectively project shots having different grain sizes to effectively increase the metal strength of the workpiece.

[0009]

【Example】

 FIG. 1 shows an embodiment of the present invention. Reference numeral 1 denotes a chamber equipped with a rotary table 3 on which a workpiece 2 is placed, and a side surface of the chamber 1 faces a pair of air nozzles 5A and 5B for projecting a shot toward the workpiece 2. 6A and 6B are first and second hoppers 6A and 6B filled with shots having different particle diameters, and are connected to air lines 9A and 9B through switching valves 8A and 8B provided at the lower outlets.

The air lines 9A and 9B to which the pressurized air is sent are also connected to the side surfaces of the hoppers 6A and 6B, respectively, and are also connected to the air nozzles 5A and 5B via the air switching valves 4A and 4B.

The discharge line 10 opened below the chamber 1 is provided with branch lines 11A and 11B connected to the hoppers 6A and 6B on the way, and the hoppers 6A and 6B are selectively switched by switching the three-way switching valve 12. Connected. Reference numeral 13 is an exhaust switching valve.

The switching valves 8A and 8B, the air switching valves 4A and 4B, and the switching valves 12 and 13 are switched and operated by the respective servo motors M, and the control device 15 controls these operations. To do. The controller 15 also controls the rotation of the motor N 1 that rotates the rotary table 3.

The operation will be described below with reference to the flowchart (FIG. 2) of the control operation executed by the control device 15 having the above-described configuration.

The first hopper 6A is filled with shots having a large grain size, and the second hopper 6B is filled with shots having a small grain size. First, a shot having a large grain size is projected onto the workpiece 2. The valve 8A and the air switching valve 4A are opened, and the switching valve 8B and the air switching valve 4B are closed.

Pressurized air from the air line 9A pushes the shot of the hopper 6A while sending the shot to the air nozzle 5A, and toward the workpiece 2 placed on the rotary table 3 from the air nozzle 5A with a large particle size. Project a shot.

The rotary table 3 rotates at a predetermined speed, and a shot is projected over the entire circumference of the workpiece 2.

When the projection of the shot having the prescribed strength (or the predetermined time) is completed, the switching valve 8A and the air switching valve 4A are first closed in order to collect the projected shot from the chamber 1. Then, the switching valve 12 on the discharge side is switched to the first hopper 6A, and the shots are collected in the first hopper 6A. The collection of this shot is performed by a conveyor or the like that constitutes the discharge line 10, regardless of the air pressure.

Next, in order to project a shot having a small particle size, the switching valve 8B and the air switching valve 4B are opened, and a shot having a small particle size from the hopper 6B is projected onto the workpiece 2 through the air nozzle 5B.

When the prescribed shot is projected, the switching valve 8B and the air switching valve 4B are closed and the shot is stopped. Next, the switching valve 12 on the discharge side is switched to the second hopper 6B, and the shots from the chamber 1 are collected in the second hopper 6B.

In this way, by projecting shots having different grain sizes to the workpiece 2 step by step, residual stress can be exerted from the processed surface to a deep place and the final surface can be smoothed.

The control device 15 automatically switches the switching valves 8A, 8B and the air switching valves 4A, 4B to switch the shots having different particle sizes. Since the hoppers 6A and 6B can collect the shots, the shot projection and the collecting operation can be easily performed.

[0022]

[Effect of the device]

 As described above, according to the present invention, a plurality of air nozzles facing a chamber for accommodating and mounting a workpiece, a plurality of hoppers filled with shots having different particle sizes, and a shot of each hopper are provided for each air nozzle. Since there are multiple air lines that send pressurized air so that they are ejected from each air line, and a switching valve that is interposed in each air line so that shots are selectively projected from each air nozzle, a single device By simply switching the shots, shots can be selectively projected from the hopper filled with the shots having a large grain size and the hopper filled with the shots having a small grain size, which effectively enhances the metal strength of the workpiece. On the other hand, installation space can be reduced, costs can be reduced, and workability can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a flow chart showing a control operation of the same.

[Explanation of symbols] 1 chamber 2 workpiece 4A air switching valve 4B air switching valve 5A air nozzle 5B air nozzle 6A hopper 6B hopper 8A switching valve 8B switching valve 9A air line 9B air line

Claims (1)

[Scope of utility model registration request] 1. A plurality of air nozzles facing a chamber for accommodating and mounting a workpiece, a plurality of hoppers filled with shots having different particle diameters, and a shot of each hopper is added so as to be ejected from each air nozzle. A shot peening apparatus comprising: a plurality of air lines for feeding compressed air; and a switching valve interposed in each air line so as to selectively project a shot from each air nozzle.