JPH08175191A - Manufacturing method of engine mount subframe - Google Patents

Abstract

(57) [Summary] [Structure] In a subframe 3 having a substantially rectangular shape in a plan view, which is passed between side frames of a vehicle body for mounting an engine, the crossmembers 4 and 5 extending in the vehicle width direction and the vehicle body When configured with side members 6 and 7 that extend in the front-rear direction, prepare various types of side members that have different impact energy absorption performances, and select the side members appropriately as the engine or transmission changes. However, it is a method for manufacturing an engine mount sub-frame, which is characterized by being combined with a cross member. [Effect] The absorption performance (deformation performance) of impact energy can be set efficiently, and the productivity of the subframe is improved, so that the cost can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an engine mount subframe.

[0002]

2. Description of the Related Art An engine for a vehicle is generally mounted on a front portion of a vehicle body via a subframe as shown in FIG. FIG.
FIG. 6 is a perspective view of a conventional engine mount subframe. Between front side frames at the front of the vehicle (not shown)
Subframe 1 for engine mount, which is generally square-shaped when viewed from above
01 is attached, an engine 102 (including a transmission) indicated by an imaginary line is attached to the sub-frame 101, and an arm 104 for the front suspension 103 (consisting of an upper arm, a lower arm and a radius rod) is further supported. is there.

The sub-frame 101 comprises cross members 105 and 106 extending in the vehicle width direction and side members 107 and 108 extending in the vehicle front-rear direction. Mounting bolt holes 109 are provided at the four corners of the cross members 105 and 106 in plan view, and these bolt holes 109.
The sub-frame 101 is bolted between the front side frames via the.

When impact energy (external force) in the vehicle front-rear direction acts on the front bumper of the vehicle, the impact energy is mainly absorbed by the deformation of the front side frame and the sub-frame 101. In order to set the impact energy absorption performance (deformation performance) of the sub-frame 101, it is necessary to fully consider the weight of the vehicle. However, even if the vehicles are of the same vehicle type, the engine 102 and the transmission to be mounted may be changed according to the specifications, and the weight of the vehicle is significantly different due to this change. Therefore, the subframe 101 is the engine 102.
Each time the transmission or transmission is changed, it is replaced with a specific frame having different impact energy absorption performance (hereinafter, referred to as "dedicated frame").

[0005]

However, in the above-mentioned conventional structure, since the frame is dedicated, the engine 1
02 and various types of sub-frames 101 are required for each type of transmission, and it is inevitable that various types of small-scale production will be performed, resulting in poor productivity and cumbersome management, resulting in high cost.

Therefore, an object of the present invention is to provide a subframe in which the impact energy absorption performance (deformation performance) can be efficiently set and the cost is low.

[0007]

Means and Action for Solving the Problems The present inventors have
A detailed study was conducted on the function of installing the engine (including the transmission) required for the subframe, and the impact energy absorption performance (deformation performance), and it was found that the above could be shared by the cross member and the above by the side member. . Specifically, in a sub-frame having a substantially rectangular shape in plan view that is passed between side frames of a vehicle body for mounting an engine, the sub-frame is composed of a cross member extending in the vehicle width direction and a side member extending in the vehicle body front-rear direction. When configured, prepare various types of side members with different impact energy absorption performance, select a side member appropriately according to a change of engine or transmission, and combine it with the cross member. To do.

An engine mount bracket is attached to the cross member.

Further, the cross member is provided with a support member for supporting the suspension.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. “Front”, “rear”, “left”, and “right” follow the direction viewed from the driver, Fr is the front side, Rr is the rear side, L
Indicates the left side and R indicates the right side. Further, the drawings are to be viewed in the direction of reference numerals. FIG. 1 is a plan view of an engine mount sub-frame according to the present invention. Left and right front side frames (side frames) 2 and 2 extending in a vehicle front-rear direction are provided at a front portion of a vehicle body 1 indicated by an imaginary line. A sub-frame 3 is provided between the front side frames 2 and 2.

The sub-frame 3 has a substantially rectangular shape in plan view (including a cross shape), and has a cross member (front cross member 4 and rear cross member 5) extending in the vehicle width direction and side members (front cross member 4) extending in the vehicle front-rear direction. The left side member 6 and the right side member 7) are joined together. Front suspensions (suspension) 111, 11 are arranged on both left and right sides of the sub-frame 3. The front suspensions 11, 11 have arms (upper arm 12, lower arm 13, radius rod 14).

The sub-frame 3 has four corner portions in plan view (both ends of the front and rear cross members 4, 5) suspended from the front side frames 2, 2. Therefore, the engine (Fig. 2
And the front suspensions 11 and 11 are incorporated in the sub-frame 3, and the sub-frame 3 is passed between the front side frames 2 and 2 so that the vehicle body 1
It is mounted below the front part. Incidentally, 16 is a front wheel connected to the front suspension 11, and 17 is a front bumper of the vehicle.

FIG. 2 is a perspective view of an engine mount sub-frame according to the present invention, showing front and rear cross members 4, 4.
5, a support member (a lower arm bracket 21, a radius rod bracket 22) for supporting the front suspension 11 is provided, and an engine mount bracket (a transmission mount) for mounting an engine 18 (including a transmission) indicated by an imaginary line ( (Engine first bracket 24, engine second bracket 25)
Are joined by welding. Therefore, subframe 3
Has a function of supporting the suspensions 11, 11 only on the front and rear cross members 4, 5 and a function of installing the engine 18 (including the transmission). Less than,
This will be described in detail.

The front cross member 4 is provided with radius rod brackets 22 at both ends in the vehicle width direction, and a first engine bracket 24 is welded to the center and the top of the vehicle width direction. The rear cross member 5 is the first member 3
1 and the second member 35. First member 3
1 has a U-shaped plan view facing forward, and has a rear connecting portion 32,
It is composed of left and right arm portions 33, 33 extending from both left and right ends of the rear portion connecting portion 32 to the front side. The second member 35 has a downward U-shaped front view, and has an upper connecting portion 36 and left and right leg portions 3 extending downward from both left and right ends of the upper connecting portion 36.
It consists of 7,37. The left and right legs 37, 37 are joined to the left and right arms 33, 33 by welding, and the lower arms 13 (see FIG. 1) of the front suspension 11 are supported at the lower portions of these legs 37, 37. The lower arm bracket 21 is provided. Further, a second engine bracket 25 is stretched between the first and second members 31 and 35 at the center of the rear cross member 5 in the vehicle width direction and at the upper part thereof.

FIG. 3 is an exploded perspective view of an engine mount sub-frame according to the present invention. The front and rear cross members 4, 5 and the left and right side members 6, 7 are closed cross-section structures made of press-formed steel plates. It is the body. By the way, the left and right side members 6, 7 are the front bumper 11 of the vehicle.
(See Fig. 1) Impact energy (external force) in the longitudinal direction of the vehicle body
In order to facilitate the absorption of impact energy by deforming in the vehicle front-rear direction when the force acts, the rigidity is weakened as compared with the front and rear cross members 4, 5.

The left and right side members 6, 7 have their front portions joined by welding to the end portions of the front cross member 4, and their rear portions bolted to the tip portions of the arm portions 33, 33 of the rear cross member 5. (The nut 38 welded to the arm portion 33 is fixed with a bolt 39).

Next, an example of an assembling procedure (manufacturing method) of the engine mount sub-frame 3 having the above structure will be described with reference to FIG. First, as a member that constitutes the sub-frame 3, a common member that is shared when the engine 18 (including the transmission) is changed, and multiple types (two or more types) that are exchanged when the engine 18 (including the transmission) is changed Prepare separately from the replacement parts. The common members are the front and rear side members 4 and 5, and the replacement members are the left and right side members 6 and 7, and the engine bracket 24 to.
27, bolt 39 ... As the left and right side members 6 and 7, various types (two or more types) having different impact energy absorption performances are prepared. Impact energy absorption performance (deformation performance) of each side member 6, 7
Can be changed by changing the cross-sectional shape and size, the plate thickness of the steel plate, and the like.

Next, with the change of the engine 18 (including the transmission), an exchange member is appropriately selected from among various types and combined with a common member. In particular, since the weight of the vehicle varies greatly with the change of the engine 18 (including the transmission), the left and right side members 6 and 7 are selected to have the optimum impact energy absorption performance.

The front portions of the left and right side members 6, 7 are joined to the front cross member 4 by welding, and the rear portions of the side members 6, 7 are connected to the rear cross member 5 by bolts (nuts 38 and bolts 39). (Fixed) Stop. Finally, the engine brackets 24 to 27 are attached to the front and rear cross members 4 and 5.
Are joined by welding to complete the assembly of the subframe 3.
The procedure for assembling the sub-frame 3 is merely an example described in order to facilitate understanding of the configuration according to the embodiment,
It can be any procedure.

Next, the operation of the engine mount sub-frame 3 having the above structure will be described with reference to FIG. When impact energy (external force) in the front-rear direction of the vehicle body acts on the front bumper 17, the impact energy acts on the sub frame 3 via the front side frames 2 and 2. The front and rear cross members 4 and 5 of the subframe 3 are set to have higher rigidity than the left and right side members 6 and 7, and the impact energy is absorbed by the deformation of the left and right side members 6 and 7.

Even if the engine 18 (including the transmission) mounted on the left and right side members 6 and 7 changes according to the specifications of the vehicle, the weight of the engine 18 (including the transmission) is taken into consideration in consideration of the weight of the vehicle. Since the one that has the optimum impact energy absorption performance with respect to the weight of is selected, the impact energy absorption function is sufficiently achieved. The subframe 3 supports the suspensions 11 and 11 only by the front and rear cross members 4 and 5, and also has an engine 18 (including a transmission) installed therein. Therefore, the left and right side members 6, 7
Since only the function of absorbing impact energy is shared, the impact energy absorption performance (deformation performance) can be set efficiently.

Further, even if the engine 18 (including the transmission) mounted according to the vehicle specifications changes, the left and right side members 6 and 7 are appropriately selected and combined with the front and rear cross members 4 and 5. Therefore, the productivity of the subframe 3 is improved and the cost can be reduced as compared with the case where the entire subframe 3 is manufactured. Moreover, the front and rear cross members 4, 5 are the left and right side members 6, which are replacement members.
Since the structure is larger than 7, and has a complicated structure and high rigidity, it is a relatively high-cost member, and the cost of the subframe 3 can be reduced by increasing the mass production effect by using this member as a common member.

[0023]

Since the present invention is the manufacturing method as described above, it has the following effects. A method for manufacturing an engine mount sub-frame according to claim 1, wherein a sub-frame having a substantially rectangular shape in plan view passed between the side frames of the vehicle body for mounting the engine, the sub-frame being a cross member extending in the vehicle width direction. When configured with side members that extend in the front-rear direction of the vehicle body, prepare various types of side members that have different impact energy absorption performance, and select the side members appropriately as the engine or transmission changes, and cross By combining the members, the impact energy absorption performance (deformation performance) can be efficiently set, and the productivity of the subframe is improved, so that the cost can be reduced.

According to a second aspect of the present invention, there is provided a method for manufacturing an engine mount sub-frame, wherein an engine (including a transmission) is installed on a cross member by attaching an engine mount bracket to the cross member. Since the side member can share the deformation performance), the impact energy absorption performance (deformation performance) of the subframe can be set more efficiently.

According to a third aspect of the present invention, there is provided a method for manufacturing an engine mount sub-frame, in which a cross member is provided with a support member for supporting a suspension, thereby setting a side member that shares the impact energy absorption performance (deformation performance). Is easy.

[Brief description of drawings]

FIG. 1 is a plan view of an engine mount subframe according to the present invention.

FIG. 2 is a perspective view of an engine mount subframe according to the present invention.

FIG. 3 is an exploded perspective view of an engine mount subframe according to the present invention.

FIG. 4 is a perspective view of a conventional engine mount subframe.

[Explanation of symbols]

1 ... Vehicle body, 2 ... Side frame (front side frame), 3 ... Sub frame, 4 ... Cross member (front cross member), 5 ... Cross member (rear cross member),
6 ... Left side member, 7 ... Right side member, 11 ...
Suspension (front suspension), 18 ... Engine, 21 ... Support member (lower arm bracket),
22 ... Supporting member (radius rod bracket), 24
… Engine mounting bracket (first bracket for engine), 25… Bracket for engine mounting (second bracket for engine).

Claims (3)

[Claims] 1. A subframe having a substantially rectangular shape in plan view which is passed between side frames of a vehicle body for mounting an engine. The subframe includes a cross member extending in a vehicle width direction and a side member extending in a vehicle body front-rear direction. In the case where the side member is configured, various kinds of side members having different impact energy absorption performances are prepared, the side member is appropriately selected according to the change of the engine or the transmission, and the side member is combined with the cross member. A method of manufacturing a characteristic engine mount subframe. 2. The method for manufacturing an engine mount sub-frame according to claim 1, wherein an engine mount bracket is attached to the cross member. 3. The method for manufacturing an engine mount subframe according to claim 1, wherein the cross member is provided with a support member for supporting the suspension.