Patent GB-362853-A (GB)
Title: Improvements in lifting jacks for motor vehicles
IPC: B60S9/04
Filed: 1930-09-03
Abstract: 362,853. Jacking attachments on vehicles. WESSELS, J. F., 126, Am Wall, Bremen, and GERBRECHT, E., 24, Hafenstrasse, Werden, Ruhr, both in Germany. Sept. 3, 1930, No. 26305. [Class 79 (iii).] A wheel-jacking attachment on a motor vehicle comprises in combination a toothed bar in mesh with a pinion adapted to be driven by a hand or power operated shaft the rotation of which also serves to swing the bar from a horizontal to a vertical position and vice versa and means for locking the bar in the two angular end positions. In the form shown in Figs. 1 and 2, the lifting bar 3 slides in a sleeve 3a attached to a casing 1 pivoted on the operating shaft 2 which is rotatably mounted in a circular plate 10 attached to the vehicle frame. The inner end 5 of the bar is formed as a toothed rack engaging a pinion 7 formed in one with a larger pinion 8 in engagement with a pinion 9 on the operating shaft 2. The swinging movements of the casing 1 and bar are limited by a stud 11 fixed to the attachment plate 10 and passing through a segmental slot 12 in the casing. The inner end of the stud, which is formed with flattened sides, is engaged by a pivoted catch 13 to lock the device in the horizontal inoperative position, Fig. 1, or by a second pivoted catch 20, held against a stop 23 by a spring 6, in the vertical, lifting position, Fig. 2. In the initial position, Fig. 1, rotation of the operating shaft 2 brings the nose of a stepped cam 19 thereon into engagement with a pivoted arm 18 whereby a turning movement is imparted to the casing, the preliminary lost motion sufficing to enable a cam 16 attached to the gear pinion 8 to raise the arm 15 of the catch 13 thereby releasing it from the stop 11, the rack bar 3 being slightly moved at the same time to withdraw a pin 22 from the back of the second catch 20 allowing it to rest against the stop 23. When, by the thrust of the cam 19, the casing has been turned to the vertical position, Fig. 2, the arm 18 is disengaged from the cam by contact with the stop 11 whilst the catch 20 slips under the stop and locks the casing. Continued rotation of the shaft 2 thereupon extends the bar 3 until the foot 4 rests on the ground and the vehicle is raised. Upon reverse rotation, the bar is raised until the pin 22 thereon releases the catch 20 from .the stop 11 whereupon continued rotation, owing to the binding of the gears, causes the combination to return to the horizontal position, whereon the retaining catch 13 re-engages the stop 11. In the alternative construction shown in Figs. 4, 5, 6 and 7, the rack bar 3a slides in a casing 31 traversing and secured to a circular casing 1a rotatably mounted on a fixed casing 10a, the rack being operated by a pinion 7a projecting into the rotary casing 1a from the fixed casing wherein it is integral with a toothed gear 8a driven through a gear train 26, 27 from a hollow shaft 25 adapted to be rotated by a hand crank. The double gear 7a, 8a rotates on a stud 29 fixed to the base of the casing 10a and passes through a bearing sleeve 33 secured in an opening in the cover-plate 32 of the fixed casing. The base 35 of the rotary casing also has a bearing on the sleeve 33 and is connected by bolts 36 passing through segmental slots 39 in the cover-plate to a disc 37 rotatable on the sleeve 33 within the fixed casing. The rotation of the gears is utilized to swing the toothed lifting bar from the vertical to the horizontal, out-of-use, position and vice versa. In withdrawing the bar 3a after use, as soon as it is fully retracted into the casing 31 continued rotation of the pinion 7a pulls the rack round into the ho,rizontal position, the casing 1a rotating therewith. The reverse movement, from the horizontal to the vertical position, is effected by connecting the casing 1a to the toothed gear 8a by means of a pin 42 adapted to be projected into a bore 58 in the gear wheel. The pin passes through holes in the baseplate 35 of the casing 1a and in the disc 37 and through one of the segmental slots 39 in the fixed cover-plate 32. It is provided with lugs 43 resting on a bifurcated arm 44 of an angle lever pivoted in brackets attached to the baseplate 35, the other arm 46 of the angle lever protruding through an aperture in the baseplate into the segmental slot 39. Under the action of a spring 41, the pin 42 is protruded into the bore 58 in the gearwheel 8a for so long as the arm 46 is free in the slot 39. The slot 39 is so arranged that the connection is operative when the rack is in the horizontal position and is maintained until it has been brought down to the vertical position when the arm engages the end of the slot and disconnection is effected, continued rotation of the gears then serving to extend the rack to lift the vehicle. The angular limit positions of the rack are determined by screwed stops 62, 63. The limit of extension is determined by a spring-pressed catch 66 pivoted at 67 in the wall of the casing 31 and engaging a notch at the upper end of the rack bar. To prevent displacement from the vertical whilst the jack is in operation a stop or guide block 60 attached to the fixed cover-plate 32 projects through a segmental slot 61 in the rotary plate 35 into alignment with the rack casing 31 so that the rack and casing can only be rotated when the rack bar has been fully retracted to bring a flared transverse channel 59 therein into alignment with the stop 60, the stop obstructing rotation at other times. To prevent retrograde or wrong movements during either raising or lowering operation of the rack bar, a pair of detents 48, 49, Fig. 7, drawn together by a spring 51 engage, one or the other, under the control of a cam or eccentric 53, with the driving pinion 26, to render the movement thereof unidirectional. The cam is fixed to the end of a spindle 52 passing through the hollow shaft 25, Fig. 5, and formed with a notch 57 in its end enabling the cam to be set by a preliminary movement of the operating hand crank. When the rack bar is being lowered, the detent 48 engages the pinion to prevent reverse movement. To return the device to the inoperative position the detent 49 is put into operation and serves to hold the parts in the horizontal, outof-use, position. The parts of the apparatus are so distributed that the centre of gravity coincides substantially with the axis about which it rotates. The rotary casing 1a is flanged to overlap the fixed casing at 34 and may have frictional engagement therewith to steady the movements. To take the weight of the wheels off the vehicle springs before the lifting device is brought into operation, rotary cranked members 79, Fig. 8, are mounted in brackets 75 adjacent to the axles 72 and are connected by cords &c. 69, 70 to the inner disc 37 attached to the casing 1a so that during the initial rotary movement of the casing, the members 79 are turned in opposition to springs 77 to bring the lower arms 76 thereof under the axles.