JP3525315B2 - Joint structure of two steel plates - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a joint structure by welding two steel plates.

[0002]

2. Description of the Related Art To join two steel plates by welding,
There are various means. The present invention relates to a structure in which a second steel plate is superposed on the surface of a first steel plate, and side edges of the second steel plate are welded to the surface of the first steel plate.

[0003]

When this kind of joining is carried out by arc welding, the applied voltage and other conditions are not stable at the starting point and the ending point of the welding, and the torch is moved or stopped. There is a possibility that a welding failure such as perforation or non-welding may occur on the side of the first steel sheet due to a timing deviation from the arc generation timing or the like. In particular, when the first steel plate is a thin plate, there is a high risk of perforation, and when the shape of the portion to be welded of the first or second steel plate is uneven due to drawing or the like, However, there is a high possibility that the above-mentioned welding failure will occur.

In order to eliminate such a fear, the starting point and the ending point of welding are set inside the edge of the second steel sheet, the torch is once moved from the starting point to the edge of the second steel sheet, and then along the edge. After moving it, it may be moved from the edge toward the inside of the second steel plate. However, it is not preferable to move the torch in a U-shape in this way, in terms of automating the welding work, because of problems such as complicated operation procedures and an increase in auxiliary equipment such as a transverse feed device of the torch. .

In view of the above problems of the prior art, the present invention can solve the problems at the starting point or the ending point of welding, simplify the welding work, and easily automate the two work pieces. It is intended to provide a joint structure of steel plates.

[0006]

According to the present invention, the above problems can be solved as follows. (1) In a joint structure of two steel plates formed by superimposing a second steel plate on the surface of the first steel plate and welding the side edges of the second steel plate to the surface of the first steel plate, the second steel plate At a portion which is a starting point or an end point of welding in, a projecting piece parallel to the surface of the first steel plate is provided so that the end of the welded part ends within the projecting piece.

(2) In the above item (1), projecting pieces are provided at the starting and ending points of welding in the second steel plate,
A weld is formed over a range that connects the points in both the projecting pieces and extends along the edge of the second steel plate sandwiched between the points.

(3) In the above item (1) or (2), the plate thickness of the second steel plate is made larger than the plate thickness of the first steel plate.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. In this embodiment, a reinforcing plate (1), which is a first steel plate fixed to the lower surface of the front end of a hood of an automobile, is a second steel plate in which a secondary latch (not shown) of the hood lock device is disengaged. The present invention is applied to a welded portion when fixing the plywood (2).

The reinforcing plate (1) is bent in an expanded U shape in a side view, and a window hole (3) elongated in the left-right direction is formed in the center of the bottom piece (1a) thereof.

The lower half of the striker (4) formed by bending a steel bar into a U-shape in a side view is fitted into the window hole (3), and the lower half of the striker (4) is erected before and after the striker (4). The upper half part of the part (4a) is a raised part (1c) (1d) formed on the inner surface of the front piece (1b) slightly inclined forward and the rear piece (1c) slightly inclined rearward of the reinforcing plate (1). It is fixed by welding. When the hood is closed, the striker (4) enters a striker entry groove (not shown) of the hood lock device provided on the vehicle body side and engages with a primary latch (not shown) in the hood lock device. By doing so, the hood can be restrained in the closed state.

The engagement plate (2) is formed by drawing a thicker steel plate than the reinforcing plate (1) and hangs down through the right end of the window hole (3) and is secondary to the lower end. An engaging portion (2a) having a substantially L-shaped cross-section so that the latch can engage with it, and a flange piece (a flange continuous with a front edge, a rear edge and an outer edge of the upper end of the engaging portion (2a)). 2b) (2c) (2d) are provided.

An elongated rectangular notch (5) is formed in the center of the free edge of each flange piece (2b) (2c) (2d).
By forming (5), each flange piece (2b) (2c) (2d)
Projecting pieces (6) and (6) are formed on both sides of the notch (5) at the free end of the.

In the engaging plate (2), the engaging portion (2a) protrudes downward from the lower surface of the reinforcing plate (1) through the window hole (3), and each flange piece (2b) (2c) (2d) and them. The protrusion (6) provided on the
Protrusions (1f) (1g) formed on the inner surfaces of the front piece (1b) and the rear piece (1c) of the reinforcing plate (1) and on the upper surface of the bottom piece (1a), respectively.
It is held so as to polymerize in (1h), and in that state, FIG.
As shown in, the flange pieces (2b) (2c) (2d) at the free end of the pair of protrusions (6) (6), in this example, set in the middle of the base of each protrusion (6) Move the torch (not shown) along a straight line (L) that connects the starting point (P1) and the ending point (P2) and that matches or is close to the edge (5a) that is the bottom of the notch (5). By doing so, a welded portion (7) having a required width centered on the straight line (L) as shown by an imaginary line in FIG. 2 is formed. That is, each end of the welded portion (7) terminates at an intermediate portion of the base of the projecting piece (6), and the intermediate portion extends along the edge (5a).

The welded portion (7) is preferably linear as described above, but the edge (5a) to be welded.
If is a curved line or a line with a bent portion, it is preferable to make a curved line or a bent line along it.

Further, the projecting piece (6) may be provided only on one of the starting point and the ending point of welding, where welding failure is likely to occur, and the other may have a structure similar to the conventional one, depending on the working conditions.

With the joining structure as described above, it is less likely that perforations will occur on the side of the reinforcing plate (1), which is a thin plate, due to excessive heating at the starting point and the ending point of welding, and there will be poor welding due to insufficient heating at this portion. Even if the problem occurs, if the original effective welding range is set in advance to a range excluding the protruding piece (6), there is no risk of insufficient strength.

Further, by providing the projecting piece (6), the welding range can be clearly known, and by the projecting piece,
There is also an effect that thermal distortion due to welding and deformation of the steel sheet during welding can be suppressed.

[0019]

According to the present invention, the following effects can be obtained. (1) The welding conditions are not stable. Since the projecting pieces are provided at the starting point and the ending point of the welding and the welding is started and ended from here, the first piece due to excessive heating at these portions is used. It is possible to prevent perforations in the steel sheet and other welding defects, and it is possible to effectively perform welding along the original edge of the second steel sheet under stable welding conditions.

(2) Since the projections are provided at the start point or the end point of the welding, the range to be welded can be easily and clearly known, and the work can be speeded up.

(3) The projecting piece can suppress thermal strain due to welding and deformation of the steel sheet during welding.

(4) It is not necessary to bend the movement path of the torch in a U-shape as in the conventional case, and it is possible to make a simple linear shape. Therefore, the operation procedure is simplified and the auxiliary equipment is reduced. It is possible to easily automate the welding work. (Each of the above effects of the invention of claim 1).

(5) When the projecting pieces are provided at both the start point and the end point of welding as in the invention of claim 2, the above effects can be exhibited at both ends of the welded portion. Especially 1
Since the range to be welded can be determined by the pair of projecting pieces, the welding operation can be performed easily and quickly by visual inspection.

(6) According to the invention of claim 3, the first
If the plate thickness of the steel plate is less than the plate thickness of the second steel plate, the first
The effect is great in that it can prevent perforation of the steel sheet.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is an enlarged front view of a waist of the same.

[Explanation of symbols]

(1) Reinforcement plate (first steel plate) (1a) Bottom piece (1b) Front piece (1c) Rear piece (1d) (1e) (1f) (1g) (1h) Raised part (2) Engagement plate (second steel plate) (2a) Engagement part (2b) (2c) (2d) Flange piece (3) Window hole (4) Strike (4a) Standing part (5) Notch (5a) Edge (6) Projection piece (7) Welded part (P1) Start point (P2) End point (L) Straight line

Claims (3)

(57) [Claims] 1. A joining structure of two steel plates, wherein a second steel plate is superposed on the surface of the first steel plate, and side edges of the second steel plate are welded to the surface of the first steel plate. 2 is characterized in that a projecting piece parallel to the surface of the first steel sheet is provided at a portion which becomes a starting point or an ending point of welding in the steel sheet, and the end of the welded portion ends within the projecting piece. Bonding structure of one steel plate. 2. Protrusions are provided at the starting and ending points of welding in the second steel plate, the points in both protrusions are connected, and the range along the edge of the second steel plate sandwiched between the protrusions is connected,
The joined structure of two steel plates according to claim 1, wherein a welded portion is formed. 3. The joining structure of two steel plates according to claim 1, wherein the plate thickness of the second steel plate is larger than that of the first steel plate.