On-vehicle unit

Abstract

To provide an on-vehicle unit which can satisfy collision performance without deteriorating mountability to a vehicle.SOLUTION: A T-shaped buffering member 70 which is constituted of a longitudinal member 72 and a vertical member 74 vertically extending with respect to the longitudinal member 72 from a center portion of the longitudinal member 72 is arranged inside an on-vehicle unit 50. A collision load applied to the on-vehicle unit 50 is dispersed to an electric motor chamber holding portion 40b2, a gear chamber holding portion 40a1 and a connecting shaft 14 in a gear chamber Rg by the buffering member 70, and also, the collision load is dispersed to a region other than an electric motor chamber Rm. Therefore, a risk such as the damage of an electric motor MG is reduced, and accordingly, the on-vehicle unit 50 which can satisfy collision performance can be provided without deteriorating mountability to a vehicle 10.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an in-vehicle unit. [Background technology]

[0002] A well-known vehicle-mounted unit includes an electric motor, a power transmission device that transmits the power of the electric motor to driving wheels, and a case that integrally houses the electric motor and the power transmission device. For example, a power unit is described in Patent Document 1. Patent Document 1 discloses the shape and structure of an external additional cover that protects a high-voltage portion (electric motor) of the vehicle-mounted unit from a collision load. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-73769 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in protecting the high-voltage portion (motor) of the vehicle-mounted unit from a collision load, providing a protective cover or protective member on the outside of the vehicle-mounted unit has a problem in that it deteriorates the mountability on the vehicle.

[0005] The present invention has been made against the background of the above circumstances, and its object is to provide an in-vehicle unit that can satisfy collision resistance performance without compromising mountability in a vehicle by setting a protective member inside. [Means for solving the problem]

[0006] The gist of a first aspect of the present invention is an in-vehicle unit including: (a) an electric motor; a power transmission device that transmits power of the electric motor to driving wheels; a buffer member for protecting the electric motor from a collision load; and a case that houses the electric motor, the power transmission device, and the buffer member, wherein (b) the case includes an electric motor chamber that houses the electric motor, and a gear chamber that houses the power transmission device, and (c) the buffer member includes a longitudinal member and a longitudinal member extending from a center portion of the longitudinal member to the longitudinal member. The longitudinal member is a T-shaped member composed of a vertical member extending vertically, and the longitudinal member is located inside the case on the side that receives the collision load rather than the motor, and is held by a motor chamber holding portion that is provided in the motor chamber and holds one end of the longitudinal member, and a gear chamber holding portion that is provided in the gear chamber and holds the other end of the longitudinal member, and further, a tip of the vertical member is positioned in a position that abuts against the shaft in the gear chamber when the collision load is applied. Effect of the Invention

[0007] According to the first invention, the buffer member is a T-shaped member composed of a longitudinal member and a vertical member extending perpendicularly to the longitudinal member from the center of the longitudinal member, the longitudinal member being located inside the case on the side receiving the collision load from the motor, and being held by a motor chamber holding part provided in the motor chamber and holding one end of the longitudinal member, and a gear chamber holding part provided in the gear chamber and holding the other end of the longitudinal member, and further, the tip of the vertical member is positioned to abut against the shaft in the gear chamber when the collision load is applied. As a result, the collision load is distributed to the motor chamber holding part, the gear chamber holding part, and the shaft in the gear chamber, and the risk of damage to the motor is reduced by distributing the collision load to parts other than the motor chamber. Therefore, it is possible to provide an in-vehicle unit that can satisfy collision resistance performance without deteriorating the mountability in the vehicle. [Brief description of the drawings]

[0008] [Figure 1]1 is a diagram illustrating an example of an electric vehicle equipped with an on-board unit to which the present invention is applied; [Diagram 2] FIG. 1 is a diagram illustrating a schematic configuration of a conventional vehicle-mounted unit. [Diagram 3] 1 is a diagram illustrating an example of a schematic configuration of an in-vehicle unit to which the present invention is applied; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. EXAMPLES

[0010] Fig. 1 is a diagram illustrating an example of an electric vehicle 10 equipped with an on-board unit to which the present invention is applied. Fig. 1(a) is a diagram illustrating an example of a schematic configuration of the electric vehicle 10. In Fig. 1(a), the electric vehicle 10 is an electric car equipped with an electric motor MG that functions as a power source. The electric vehicle 10 also includes drive wheels 12, a drive shaft 28, and an on-board unit 50.

[0011] The vehicle-mounted unit 50 includes an electric motor MG and a power transmission device 16 .

[0012] The electric motor MG is a known rotating electric machine having a function as a motor that generates mechanical power from electric power and a function as a generator that generates electric power from mechanical power, and is a so-called motor generator.

[0013] The power transmission device 16 is a device that transmits the power output from the electric motor MG to the drive wheels 12 via a drive shaft 28, and is internally provided with a reduction gear group and a differential mechanism (not shown). A connecting shaft 14 that is an input shaft of the power transmission device 16 is connected to a rotor shaft of the electric motor MG, and the power output from the electric motor MG is transmitted to the power transmission device 16. The power transmitted to the power transmission device 16 is converted into a driving force for running by the reduction gear group and differential mechanism inside the power transmission device 16, and is transmitted to the drive wheels 12 via a drive shaft 28 that is connected to an output shaft (not shown) of the power transmission device 16.

[0014] The power transmission device 16 has a first axis CL1 and a second axis CL2 that are parallel to each other. The first axis CL1 is a rotation axis of the electric motor MG and the connecting shaft 14. The second axis CL2 is a rotation axis of the drive shaft 28.

[0015] 1(b) is a diagram illustrating an example of an electrical configuration of the electric vehicle 10, particularly an electrical configuration related to control of the electric motor MG. In FIG. 1(b), the electric vehicle 10 includes a high-voltage battery 30 and an inverter 32.

[0016] The high-voltage battery 30 is a chargeable and dischargeable DC power source, such as a secondary battery such as a nickel-metal hydride secondary battery or a lithium-ion battery. The high-voltage battery 30 is connected to an inverter 32. The high-voltage battery 30 supplies stored electric power to the electric motor MG via the inverter 32. In addition, the high-voltage battery 30 is supplied with electric power generated by regenerative control of the electric motor MG via the inverter 32.

[0017] The inverter 32 is operated by a command from a motor control device (not shown). The inverter 32 is a power control device that controls the power exchanged between the high-voltage battery 30 and the motor MG, and is an inverter assembly for controlling the motor MG. The inverter 32 converts a direct current from the high-voltage battery 30 into an alternating current for driving the motor MG. The inverter 32 also converts an alternating current generated by the motor MG using regenerative braking into a direct current.

[0018] Fig. 2 is a diagram illustrating a conventional example of a schematic configuration of the vehicle-mounted unit 50. Fig. 2 is a plan view of the vehicle-mounted unit 50 as viewed from above in the vertical direction.

[0019] In FIG. 2, a case 40 is a non-rotatable case that is a non-rotating member that is attached to the vehicle body, and houses the electric motor MG and the power transmission device 16 therein.

[0020] The case 40 includes a housing 40a as a first case, a case body 40b as a second case, and a cover 40c as a third case. The housing 40a and the case body 40b are integrally connected by fasteners such as bolts so that an open portion on the left side of the drawing of the housing 40a and an open portion on the right side of the drawing of the case body 40b are aligned. The case body 40b and the cover 40c are integrally connected by fasteners so that the open portion on the left side of the drawing of the case body 40b is covered by the cover 40c.

[0021] The case body 40b is a case including a partition wall 40b1 that separates an electric motor chamber Rm that houses the electric motor MG from a gear chamber Rg that houses the power transmission device 16. In the case 40, the gear chamber Rg is formed by joining the housing 40a and the case body 40b, and the electric motor chamber Rm is formed by joining the case body 40b and the cover 40c.

[0022] The main body of the electric motor MG is fixed non-rotatably in the electric motor chamber Rm, and a rotor shaft MGr integrated with the rotor, which is the rotating body of the electric motor MG, is rotatably supported by a bearing 44. In addition, preferably, the inverter 32 may be housed in the electric motor chamber Rm at the same time.

[0023] The gear chamber Rg houses the power transmission device 16. A connecting shaft 14, which is the input shaft of the power transmission device 16, is connected to the rotor shaft of the electric motor MG, and the connecting shaft 14 is rotatably supported by a bearing 42. In addition, a group of reduction gears (not shown) and a rotating shaft of a differential mechanism inside the power transmission device 16 are also rotatably supported by bearings (not shown).

[0024] Incidentally, the electric motor MG housed in the electric motor chamber Rm is a component that operates at high voltage and high current. For example, a measure is required to prevent the electric motor chamber Rm from being directly subjected to a collision load, so that the inside or connection terminals of the electric motor MG are not damaged or exposed due to a collision load, which may cause a short circuit or leakage current. For example, as shown in FIG. 2, when a collision load is expected to be applied from the upper side of the paper, a buffer member 62 is provided outside the vehicle-mounted unit 50 (case 40) to hold the collision load between the housing fixing part 60 of the vehicle 10 and the housing 40a (gear chamber Rg). However, the measure on the outside of the vehicle-mounted unit 50 (case 40) has a problem in that it is difficult to mount the unit on the vehicle.

[0025] Therefore, in this embodiment, a measure is taken to incorporate a buffer member 70 in the case 40 as shown in Fig. 3. Fig. 3 is a plan view of the vehicle-mounted unit 50 as seen from above in the vertical direction, similar to Fig. 2. The same reference numerals are used for the parts common to Fig. 2, and the description thereof will be omitted. The buffer member 70 is a T-shaped member composed of a longitudinal member 72 parallel to the connecting shaft 14, and a vertical member 74 extending integrally from the center of the longitudinal member 72 perpendicularly to the longitudinal member 72. The longitudinal member 72 of the buffer member 70 is disposed inside the case 40 on the side receiving the collision load from the electric motor MG, that is, on the upper side of the paper surface of the case 40 in Fig. 3. The cushioning member 70 is held within the case 40 by having one end 72a held by a motor chamber holding portion 40b2 formed in the motor chamber Rm (case body 40b) and the other end 72b held by a gear chamber holding portion 40a1 formed in the gear chamber Rg (housing 40a). A tip end 74c of a vertical member 74 of the cushioning member 70 is located near the connecting shaft 14 within the gear chamber Rg and is disposed so as to come into contact with the connecting shaft 14 when a collision load is applied.

[0026] 3, when a collision load is applied from the upper side of the paper in a direction perpendicular to the first axis CL1, the load is first applied to the longitudinal member 72 of the buffer member 70, and then the load applied to the longitudinal member 72 is distributed to the motor chamber holding part 40b2 and the gear chamber holding part 40a1 which hold one end 72a and the other end 72b of the longitudinal member 72, and then the center part of the longitudinal member 72 is pushed downward on the paper and the tip part 74c of the vertical member 74 abuts against the connecting shaft 14, so that the load is also distributed to the connecting shaft 14, and the load input to the connecting shaft 14 is distributed from the bearing 42 to the gear chamber Rg (housing 40a). As a result, the collision load is distributed to parts other than the motor chamber Rm, so that the risk of damage to the electric motor MG can be reduced.

[0027] The cushioning member 70 is preferably made of a metal material, but other materials may be used as long as they have sufficient crashworthiness, and a composite material may also be used.

[0028] As described above, according to this embodiment, the collision load is distributed among the motor chamber holding portion 40b2, the gear chamber holding portion 40a1, and the connecting shaft 14 in the gear chamber Rg, and the risk of damage to the motor MG is reduced by distributing the collision load to portions other than the motor chamber Rm. Therefore, it is possible to provide an in-vehicle unit 50 that satisfies collision resistance performance without deteriorating the mountability on the vehicle 10.

[0029] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention can be applied to other embodiments.

[0030] For example, the tip 74c of the vertical member 74 protruding from the elongated member 72 may be held by a holding portion formed on the partition wall 40b1, so that the buffer member 70 is held at three points.

[0031] In the above embodiment, the vehicle 10 is an electric vehicle, but the present invention is not limited to this. For example, the present invention can be applied to a hybrid electric vehicle that has an engine and an electric motor as a power source.

[0032] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various modified and improved forms based on the knowledge of those skilled in the art. [Explanation of symbols]

[0033] 12: Drive wheel 14: Connecting shaft (shaft) 16: Power transmission device 40: Case 40a1: Gear chamber holding portion 40b2: Motor chamber holding portion 50: Vehicle-mounted unit (Vehicle-mounted unit) 70: Cushioning member 72: Long member 72a: One end portion 72b: Other end portion 74: Vertical member 74c: Tip portion MG: Motor Rm: Motor chamber Rg: Gear chamber

Claims

[Claim 1] An in-vehicle unit including an electric motor, a power transmission device that transmits power of the electric motor to driving wheels, a buffer member that protects the electric motor from a collision load, and a case that houses the electric motor, the power transmission device, and the buffer member, the case includes a motor chamber that houses the motor and a gear chamber that houses the power transmission device, The buffer member is a T-shaped member including a longitudinal member and a vertical member extending perpendicularly to the longitudinal member from a central portion of the longitudinal member, the longitudinal member is located inside the case on a side receiving the collision load relative to the motor, and is held by a motor chamber holding portion provided in the motor chamber and holding one end of the longitudinal member, and a gear chamber holding portion provided in the gear chamber and holding the other end of the longitudinal member, The vehicle-mounted unit further comprises a tip of the vertical member disposed at a position where the tip comes into contact with a shaft in the gear chamber when the collision load is applied.

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