JPS6327139Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a bearing case mounting structure for a crankshaft front bearing used in a press.

Conventionally, the crankshaft, which was installed facing the front and back direction of the press, had a bearing fitted into the rear body, and the front body had a round hole partially cut out at the bottom to pass the crankshaft through. After supporting the crankshaft inserted from above with the rear bearing, insert the bearing of the bearing case with the front bearing fitted into the crankshaft, insert the bearing case into the round hole, and attach the flange of the bearing case to the side of the machine. was. When this crankshaft is subjected to upward force due to press working, there is no problem as the upper semicircle of the round hole receives the bearing case, but if a breakthrough occurs during punching, the upward force applied to the crankshaft is As the force in the direction is suddenly removed, the body of the press, which was being pulled by the force in the upward direction, suddenly contracts. As a result of this reaction, the crankshaft receives a large downward force and applies an opening force to the notch of the round hole through the front bearing and the bearing case. This causes the bearing case to move slightly downward, which is a factor that lowers the accuracy of press-formed products.

The purpose of this invention is to eliminate this drawback by supporting the outer periphery of the bearing case with a round hole and supporting the outer periphery of the flange with the machine body, thereby creating a structure that is strong against breakthroughs and reducing the precision of press working. An object of the present invention is to provide a bearing case mounting structure for a crankshaft front bearing that can prevent the above problems. Embodiments of the present invention will be described below with reference to the drawings.

1, 2, and 3 show the structure of a machine body 2 that rotatably supports a crankshaft 1 of a press. The rear side of the crankshaft 1 is supported by a bearing 3 directly fitted into the body 2. The front side of the crankshaft 1 is supported by a bearing 5 provided in a bearing case 4 attached to a machine body 2. Connecting rod 6 is attached to crank pin 1a of crankshaft 1.
The upper ends of are connected. The lower end of the conrod 6 is connected to a press slide (not shown),
As the crankshaft 1 rotates, a slide guided by a body 2 is raised and lowered. A main gear 7 is fixed to the rear end of the crankshaft 1 with a key. As shown in FIG. 3, the front body 2 to which the bearing case 4 is attached has a round hole 8 into which the outer diameter portion 4a of the bearing case 4 is fitted, and a seat into which the outer periphery of the flange 4b of the bearing case 4 is fitted. The boreholes 9 are provided so as to fit with each other with a small clearance. The round hole 8 is a through hole, and a notch 8a is provided on the lower side through which the crank pin 1a of the crankshaft 1 can pass. A pointer 10 is attached to the front end of the crankshaft 1 to indicate the crank angle.

Next, we will discuss the effect. When a press performs press processing, a connecting rod 6 is attached to the crankshaft 1.
An upward force is applied through the bearings 3 and 5,
An upward force is applied to the body 2 via the bearing case 4. At the same time, a downward force is applied to the bed side of the press, and a tensile force is applied vertically to the machine body 2. At this time, the force acting on the front side of the crankshaft 1 is transmitted from the bearing 5 to the bearing case 4.
and is transmitted to the fuselage 2 from the outer periphery of the flange 4b. When a breakthrough occurs in the press process and the tensile force applied to the machine body 2 is suddenly released,
A downward force is applied to the crankshaft 1 due to the reaction.
This downward force is transmitted to the bearing case 4 via the front bearing 5.
However, since the flange 4b of the bearing case 4 fits into the counterbore hole 9 of the fuselage 2 with a small clearance, the transmission is smoothly transmitted to the fuselage 2, and there is a notch on the lower side of the round hole 8 of the fuselage 2. Even if there is a notch 8a
Do not apply excessive force that would expand the Therefore, the precision of the pressed product is not reduced.

As is clear from the above explanation, according to the present invention, a counterbore hole is provided in the machine body into which the outer periphery of the flange of the bearing case fits, so there is no risk of the notch of the round hole opening, which reduces the accuracy of press processing. Therefore, it has great practical effects and advantages, such as saving press repair costs and improving press operation rate.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional side view of the main parts of the press according to the embodiment, FIG. 2 is a front view thereof, and FIG. 3 is a front view of the main parts of the machine body. 1 is the crankshaft, 2 is the body, 3 is the bearing, 4 is the bearing case, 4a is the outer diameter part, 4b is the flange, 5 is the bearing, 6 is the rod, 7 is the main gear, 8 is the round hole,
8a is a notch, 9 is a counterbore, and 10 is a pointer.

Claims (1)

[Claims for Utility Model Registration] In the structure of the front bearing part that rotatably supports the crankshaft provided facing the front and back direction of the press, the front bearing 5 is installed in the hole, and a flange is attached to the outer diameter part 4a. 4b, a round hole 8 provided in the body of the press, into which the outer diameter part 4a of the bearing case 4 fits, and has a notch 8a for passing the crankshaft; A bearing case mounting structure for a front crankshaft bearing, comprising: a counterbore hole 9 which is provided concentrically with the hole 8 and into which the outer periphery of a flange 4b of a bearing case 4 is fitted with a small clearance;