AU646959B2 - Gear-box suspension for railway motor car - Google Patents

Description

P/00/011 28/5191 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 646,9459

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Application Number: Lodged: Invention Title: GEAR-BOX SUSPENSION FOR RAILWAY MOTOR CAR The following statement is a full description of this invention, Including the best method of performing it known to TITLE OF THE INVENTION Gear-box suspension for railway motor car BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to an improvement of a gear-box suspension for railway motor car.

2. DESCRIPTION OF THE PRIOR ART A conventional gear-box suspension for railway motor car, for example, shown in Published Unexamined Japanese Utility Model Application Sho 51-109508 is described referring to FIGs.5 to is a side view of a railway motor car in general. As shown in FIG.5, a body 12 of the railway motor car is mounted on bogies 1, and axle springs 11 of the bogies 1 are compressed by the load of the body 12.

FIG.6 is a plan view showing a constitution of a bogie 1 having parallel Cardan drive devices with bogie mounted motors. In FIG.6, traction motors 3 are directly mounted on a bogie frame la in a manner that rotation shafts 3a of motors 3 are to be parallel to axles 2.

Reduction gear devices 4 are directly borne on the axles 2 by bearings (not shown in the figure). The shafts 3a of the motors 3 are coupled to the reduction gear devices 4 via Cardan joints 5. (In this specification, the words "Cardan joint" includes any type of flexible joint, such as geared-type flexible joint.) FIG.7 is a side view showing the conventionally suspended reduction gear device 4. In FIG.7, a gear-box 4a is suspended on the axle 2 via a bearing 2a. A larger gear 8 is fixed on the axle 2. A smaller gear 9, which is engaged with the larger gear 8, is coupled to the motor 3 via the Cardan joint 5. Therefore, a driving torque of the motor 3 is transmitted to the axle 2 via a reduction gear train of the larger and smaller gears 8 and 9. For supporting the reaction torque, the gear-box 4a is suspended on the bogie frame la via a suspension arm 7 and a suspension base 6 in a side of the smaller gear 9.

FIG.8 is a partially sectional view showing a constitution of the conventional gear-box suspension on a bogie. In FIG.8, the suspension arm 7 is mounted on the i I suspension base 6 of the bogie frame la via rubber vibration isolators 13, washers 1.4 and 16, shims 15 and a nut 17. The washers 14 directly contact the rubber vibration isolators 13 for supplying tightening force.

The shims 15 are placed between the washers 14 and 16.

The nut 17 is engaged with a screw part 7a of the suspension arm 7 whereby the suspension arm 7 is fixed on the bogie frame la.

In such a parallel Cardan drive device, a relation designated by the following equation holds among deflections D (not shown in the figure)of the axle springs 11, a deflection C (not shown in the figure) of the Cardan joint 5, a distance A between the center axes of the gears 8 and 9 in FIG.7 and a distance B between the center axis of the axle 2 and the center of a fulcrum 7s of the suspension arm 7 in FIG.7: A)/B]xD As is apparent from the above-mentioned equation, in order to sufficiently reduce the deflection C of the Cardan joint 5 with respect to the deflection D of the axle spring, the distance B should be made as close as the distance A. However, such a scheme has a disadvantage which is described below in detail.

As shown in FIG.5, when a body 12 of the railway motor car is mounted on bogies 1, axle springs 11 of the bogies 1 are compressed by the load of the body 12. Since the motor 3 shown in FIG.6) is directly-fixed on the bogie frame la of the bogie 1, the motor 3 is displaced lower with regard to the axle 2 by the same distance as the deflection of the axle springs 11.

On the other hand, the smaller gear 9 coupled with the larger gear 8 is borne by a bearing on the gear box 4a, which is suspended on the axle 2. Therefore, the center axis of the smaller gear 9 is substantially stationary with respect to the axle 2. When the axle springs 11 are compressed by the load of the body 12, the center axis of the smaller gear 9 shown in FIG.7 is displaced upward relative to the center axis if the shaft 3a of the motor 3. The relative displacement C between the center axis of the smaller gear 9 and the center axis of the shaft 3a of the motor 3 is proportional to the deflection D of the axle springs 11 (shown in FIG.5) by the ration of as indicated in the above-mentioned equation In other wards, the displacement C Js proportional to the deflection D and also to the ratio of the distance which is between the center axis "X" of the smaller gear 9 and the axis of the fulcrum 7s of the suspension arm 7, against the distance B which is between the center axis of the axle 2 and the fulcrum 7s of the suspension arm 7.

Similarly, the shaft 3a of the motor 3 is relatively displaced downward in relation to the center axis of the smaller gear 9 in the saie relation of the afore-mentioned equation by the vibration during the running of the railway motor car or the getting on and off of passengers.

As shown in FIG.6, for assembling the driving device, the motor 3 is mounted on the bogie frame la in a manner that the center axis of the shaft 3a is higher by a predetermined small distance than the center axis of the smaller gear 9 (shown in FIG.7). The position of the suspension arm 7 is adjusted to make the center axis of the shaft 3a of the motor 3 coincide with the center axis of the smaller gear 9 when passengers of the capacity for carrying of the railway motor car get on. This is because that the smaller the deflection in the Cardan joint becomes, the larger the allowable transmitted torque of the Cardan joint 5 to the smaller gear becomes, as is shown by the characteristic curve of FIG.9.

In FIG.7, the suspension arm 7 is pivotted to the gear-box 4a by the fulcrum 7s, which is, for example, a spherical bearing. And thereby, the suspension arm 7 can be swung relatively to the gear-box 4a. As shown in FIG.8, the rubber vibration isolators 13 are compressed by the engagement of the nut 17 and the screw part 7a of the suspension arm 7, and thereby the vibration of the gearbox 4a is attenuated by the rubber vibration isolator 13 and not transmitted to the bogie frame la of the bogie 1 (shown in FIG.6). Furthermore, since a rod part 7b of the suspension arm 7 is borne by the rubber vibration isolators 13, the suspension arm 7 can be swung a little responding to upward or downward motion of the axle 2.

The shims 15 are thin plates of horseshoe shape as shown in FIG.10(C) and used laminated for adjusting position of the suspension arm 7.

In the cotventional drive device configured above, adjustment of the position of the suspension arm 7 is made by adding or taking out the (lower) shims disposed below the suspension base 6 in FIG.8.

Concretely, the nut 17 is loosened for making the rubber vibration isolators 13 free and the lower shim(s) 15 is (are) put in (added)or pulled out. The lower shim(s) which is (are) to be put in, is (are) supplied from the upper shims 15 disposed above the suspension base 6 in FIG.8.

The suspension base 6 protrudes from the bogie frame la, and a rib 6a (shown in FIG.8) is provided thereto for providing a mechanical strength which is necessary to suspend the gear-box 4a (shown in FIG.7).

Details of the suspension base 6 is shown in enlarged scale in FIGs.10(A) and The above-mentioned adjustment of the position of the suspension arm 7 is executed under a condition that the drive devices including the motor 3, gear 4 and Cardan joint 5 are mounted on the bogie 1 or a condition that the body 12 is further mounted on the bogies 1 as shown in When the body 12 does not have any access opening on the floor, the adjustment of the position of the suspension arm 7 is worked under the body 12, by looking upward condition from the underfloor of the railway motor car, Therefore, it is difficult to see the nut 17 from the underfloor working, and hence the loosening of the nut 17 is operated gropingly.

Furthermore, since the shims 15 has the horseshoe shape as shown in FIG.10(C), it is difficult to find an opening i, I_ of the shim 15 by blind operation, and it is also difficult to put in or pull out a few shims among many shims OBJECT AND SUMMARY OF THE PRESENT INVENTION Purpose of the present invention is to solve the above-mentioned problems and to provide an improved gearbox suspension for railway motor car.

A gear-box suspension for railway motor car in accordance with the present invention comprises: a bogie frame for mounting a traction motor thereon and having at least one substantially vertical surface; a gear-box being borne on an axle by a bearing and having a smaller gear and a larger gear in engagement each other wherein the smaller gear is coupled to a shaft of the motor by a Cardan joint and the larger gear is fixed on the axle; a suspension base having at least one vertical oval or oblong slot in a vertical wall and fixed on the vertical face of the bogie frame; and a suspension arm which is fixed on the suspension base at an end thereof and coupled movably with the gear-box at the other end thereof for adjusting the level difference between the center axis of the shaft of the motor and the center axis of the smaller gear.

Furthermore, knurling with horizontal grooves is provided on at least one vertical surface of the bogie frame and a coupling surface of the vertical wall of the suspension base with which coupling face the suspension case is coupled to the vertical surface of the bogie frame.

In the gear-box suspension for railway motor car in accordance with the present invention configured above, the suspension base is isolated from the bogie frame and the suspension base is fixed on the bogie frame by the screw-bolts which penetrate the vertical oval or oblong slot of the suspension base. Therefore, the height of the suspension base whereon the suspension arm is fixed is adjustable in vertical direction by changing the position of the screw-bolts relative to the vertical oval or oblong slot of the suspension base. As a result, the shims, which was hitherto used in the conventional gear-box suspension, are dispensed with in the gear-box suspension of the present invention.

Since the knurling is formed on the vertical surface of the bogie frame and the coupling fixing surface of the vertical wall of the suspension base, the relative height of the suspension base is vertically adjustable by changing the coupling of the knurled surfaces. And thereby, the position of the suspension arm is adjusted.

Furthermore, the coupling of the knurled surfaces increases fixing force for the vertical load.

While the novel features of the invention are set forth particularly in the appended claims, the invention, both as to organization and content, will be better understood and appreciated, along with other objects and features thereof, from the following detailed description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF TIE DRAWINGS FIG.1 is a plan view showing a constitution of a bogie having parallel cardan drive devices with bogie mounted motor.

FIG.2 is a side view showing an essential part of the bogie having a reduction gear device suspended by the gear-box suspension for railway motor car shown in FIG.3.

FIG.3 is a partially sectional enlarged side view showing an essential part of the first preferred embodiment of the gear-box suspension for railway motor car in accordance with the present invention.

FIG.4 is a partially sectional side view showing an essential part of a second preferred embodiment of a gear-box suspension for railway motor car in accordance with the present invlntion.

FIG.4(A) is a front view showing the essential part of the second preferred embodiment of the gear-box suspension for railway motor car in accordance with the present invention.

is the side view showing the railway motor car, in general.

FIG.6 is the plan view showing the conventional constitution of the bogie having the parallel cardan drive devices with bogie mounted motor.

FIG.7 is the side view showing the conventionally suspended reduction gear device.

FIG.8 is the partially sectional side view showing the constitution of the conventional gear-box suspension for railway motor car.

FIG.9 is the graph for showing the relation between the deflection angle of the Cardan joint 5 and the torque which is transmitted from the motor to the smaller I gear 8 by the Cardan joint is the plan view showing the conventional suspension base 6 used in the conventional gear-box suspension for railway motor car.

FIG.1O(B) is the side view showing the conventional suspension base 6 shown in is the plan view showing the shape of the shim 15 which is used in the conventional gear-box suspension for railway motor car shown in FIG.8.

It will be recognized that some or all of the figures are schematic representations for purposes of illustration and do not necessarily depict the actual relative sizes or locations of the elements shown.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first preferred embodiment of a gear-box suspension for railway motor car in accordance with the present invention is described referring to FIGs.1 to 3.

FIG.1 is a plan view showing a constitution of a bogie having parallel cardan drive devices with bogie mounted motor, wherein gear-boxes are suspended by a gearbox suspension in accordance with the present invention.

FIG.2 is a side view showing a reduction gear device suspended by the gear-box suspension for railway motor car in accordance with the present invention. FIG.3 is a partially sectional side view showing the first embodiment of a mounting part of a suspension arm 71 and a suspension base 61. In FIG.1, traction motors 3 are directly mounted on the bogie frame la in a manner that rotation shafts 3a of the motors 3 are to be parallel to axles 2. Reduction gear devices 4 are directly borne on the axles 2 by bearings (2a shown in FIG.2). The shafts 3a of the motors S 3 are coupled to the reduction gear devices 4 via Cardan joints In FIG.2, a gear-box 4a is suspended on the axle 2 via a bearing 2a. A larger gear 8 is fixed on the axle 2. A smaller gear 9, which is engaged with the larger gear 8, is coupled to the motor 3 via the Cardan joint Therefore, a driving torque of the motor 3 is transmitted to the axle 2 via a reduction gear train of the larger and 11 I smaller gears 8 and 9. For supporting the reaction torque; the gear-box 4a is suspended on the bogie frame la via the suspension arm 71 and the suspension base 61 in a side of the smaller gear 9. The suspension arm 71 and the gear-box 4a are coupled in flexible way by a spherical bearing 71s.

In FIG.3, a suspension arm 71 is mounted on a suspension base 61 via rubber vibration isolators 13, washers 16 and a nut 17. The washers 16 directly contact the rubber vibration isolators 13 for supplying tightening force. The nut 1.7 is engaged with a screw part 71a of the suspension arm 71 for fixing it on the suspension base 61.

The suspension base 61 has a vertical wall 61b. Plural vertical oval or oblong slots 19, for example four slots, Sare formed in the vicinity of the four corners on the vertical wall 61b. A bogie frame la has a vertical face 11 having female screws lla formed thereon. The suspension base 61 is fixed on the bogie frame la by screw-bolts 18, in a manner that the vertical wall 61b of the suspension base 61 contacts the vertical face 11 of the bogie frame la and the screw-bolts 18 penetrates the slots 19 and engaged with the female screws Ila on the vertical face 11. A position of a rod part 71b of the suspension arm 71 made shorter than that of the conventional case of FIG.8 by the thickness of the shims shown in FIG.8.

In the above-mentioned first embodiment, the suspension base 61 is made detachable from the bogie frame la. And the vertical position of the suspension base 61 relative to the vertical face 11 of the bogie frame la is changeable by loosening and removing the screw-bolts 18.

Therefore, the position of the suspension arm 71 is adjustable. Furthermore, since the screw-bolts 18 can be seen by worker in the underfloor of the railway motor car, the adjustment of the position of the suspension arm 71 is easily worked by a worker who looks upward.

A second preferred embodiment of a gear-box suspension for railway motor car in accordance with the present invention is described referring to FIGs.4 and FIG.4 is. a partially sectional enlarged side view showing an essential part of a second preferred embodiment Sof a gear-box suspension for railway motor car in accordance with the present invention. FIG.4(A) is a Sfront view showing the essential part of the second preferred embodiment of the gear-box suspension for ,railway motor car. In FIGs.4 and a base plate which has a receiving projection 20b at a lower end and four female-screws 20a i'n the vicinity of four corners, is fixed on the vertical face 11 of the bogie frame la. On the base plate 20, an intermediate plate 22 is mounted by screw bolts 23. The intermediate plate 22 also has female-screws 22a and a knurling 21 on a front surface. A 13 I suspension base 62 also has a knurling 62a on a back face jI which is to be coupled to the front surface of the intermediate plate 22. Pitch of the knurlings 21 and 62a is selected substantially equal to the thickness of the shim 15 used in the conventional gear-box suspension, for example, shown in FIG.8. The suspension base 82 has a vertical wall 62b. Plural vertical oval or oblong slots 19, for example four slots, are formed in the vicinity of the four corners on the vertical wall 62b. The suspension base 62 is fixed on the intermediate plate 22 by screwbolts 18 in a manner that the knurling 62a is engaged with the knurling 21 of the intermediate plate 22 and the screw-bolts 18 penetrates the slots 19 and engaged with the female screws 22a of the intermediate plate 22.

Therefore, the suspension base 62 is fixed on the bogie frame la.

In the above-mentioned second embodiment, when the tightening force of the screw bolts 18 is loosened, the suspension base 62 is vertically movable relative to the vertical face 11 of the bogie frame la. Therefore, the position of the suspension arm 71 is adjusted.

Furthermore, since the screw-bolts 18 can be seen by a worker from the underfloor position of the railway motor car, the adjustment of the position of the suspension arm 71 is easily worked by the worker who looks upward.

In the afore-mentioned first embodiment, the suspension arm 71 is coupled with the gear-box 4a by the spherical bearing 71s as shown in FIG.2. However, rubber vibration isolators, which are substantially the same as those 13 used for fixing the suspension arm 71 on the suspension base 61, are usable for coupling the suspension !I arm 71 and the gear-box 4a with a flexibility, since the relative movement of the gear-box 4a with respect to the suspension arm 71 is absorbed by the flexibility of the ;i rubber vibration isolators.

In the afore-mentioned second embodiment, by forming the knurling directly on the vertical face 11 of the bogie frame la, or the face of the base plate Thereby, the intermediate plate 22 and the base plate or the intermediate plate 22 can be omitted.

SAlthough the present invention has been i' described in terms of the presently preferred embodiments, it is to be understood that such disclosure is not to be interpreted as limiting. Various alterations and modifications will no doubt become apparent to those skilled in the art after having read the above disclosure.

Accordingly, it is intended that the appended claims be interpreted as covering all alterations and rdifications as fall within the true spirit and scope of the invention.

I.

Claims (1)

1. 3. A gear-box suspension for railway motor car in accordance with claim 1, wherein: S^ 16 Yf 6L$ 4 an intermediate plate is provided between said vertical face of said bogie frame and said vertical wall of said suspension base and knurlings are formed on respective faces of said intermediate plate and said vertical wall. DATED this 23rd day of June 1992. MITSUBISHI DENKI KABUSHIKI KAISHA WATERMARK PATENT TRDEMARK ATTORNEYS "THE ATRIUM" 290 BURWOOD ROAD HAWTHORN. VIC. 3122. 17 L ABSTRACT OF TIlE DISCLOSURE In a gear-box suspension for railway motor car, a gear-box borne on an axle is coupled with an end of a suspension arm via a spherical bearing, and the other end of the suspension arm is mounted on a suspension base which is mounted to in a manner detachable from a bogie frame. And a position of the suspension base is adjustable relative to the bogie frame. i18 18 L