US2828375A - Cam actuated switch - Google Patents

Description

March 2 5, 1958 W. HOLZER CAM ACTUATED SWITCH Filed June 13. 1955 2 Sheets-Sheet 1 cmg 3000 INVENTOR Walf'er Holzer BY: MQLAM I @2 March 25, 1958 v w. HOLZER CAM ACTUATED SWITCH 2 Sheets-Shqet 2 Filed June 13. 1955 INVENTOR Walfer Holzer United States Patent ()fiice CAM ACTUATED SWITCH Walter Holzer, Meersburg, Boden See, Germany Application June 13, 1955, Serial No. 515,127

Claims priority, application Germany June 11, 1954 1 Claim. (Cl. 200-38) This invention relates to a cam actuated switch with contacts mounted around the axle of rotation, said contacts arranged in one or several contact bearing planes behind each other, and more particularly to a cam actuated switch of common construction but provided with a clockwork mechanism which allows individual contacts to be connected by jumping into grooves respectively in a time independent manner.

A hitherto known method is to provide a time switch in addition to a cam actuated switch in order to combine untimed and timed operations. This method has the disadvantage that it requires a large amount of space and that, when applied particularly to washing and similar machines the locking of certain combinations is very difficult.

The object of this invention is to eliminate the weaknesses of the existing mechanisms and to construct the switch in such a manner, that it has the peculiar merits of taking up little space and of enabling the switching of different programmes.

The answer to the problem of the invention is that in one turning direction there is provided a system, independent of time mechanisms operating switch contacts, and in the other direction a timing switch which is constructed to operate said and/or other switch contacts.

It is a peculiar advantage of my construction that the operating shaft is fitted with a driver for the connecting and the time spring with stops limiting its path.

These stops serve to limit the effect of the connecting spring and the time spring in such a manner that the time spring on the switching side and the connecting spring on the timing side are already inoperative in the braking mechanism, but that in the rest position the connecting spring imparts a pre-tension to the operating shaft.

For the efficiency of the invention it is, moreover, important that when the knob is turned in one or the other direction two springs, preferably helical springs of different strengths will be tightened or loosened in opposite directions, and that the accumulated energy, on the spring side, overcomes a braking mechanism and contact springs and, on the switching side, contact springs, and that in the rest position the operating shaft holds stable against the time springs lying on their stop.

This feature of the construction enables a construction of the switch particularly free from vibration, which is of great importance, especially in the application of the invention to laundry or dish-washing machines.

One preferred embodyment of my invention will be apparent from the accompanying drawings in which:

Fig. 1 shows the switch fitted together,

Fig. 2 shows a structural element of the switch according to Fig. 1,

Fig. 3 shows another structural element of the switch according to Figure 1,

2,828,375 Patented Mar. 25, 1958 Fig. 4 shows the same structural element with the parts fitted in,

Fig. 5 shows, in order, how the parts are fitted onto the operating shaft, the corresponding parts being marked Fig. 5a, b, c, d, e, f and Fig. 50 showing the operating shaft as such,

Fig. 6 shows the driver on the operating shaft,

Fig. 7 shows the clockwork mechanism,

Fig. 8 shows in a diagram the torsional moments of the time spring, the connecting spring and the stop spring, as are on principle existing on the one or the other side and depending on the path when the switch is turned.

In Fig. 1 number 1 indicates the structural element in which the switch contacts together with the contact springs are fixed, electrically separate from the other parts. 2 indicates the terminals for the electric connections. By lengthening the operating shaft and fitting appropriate drivers as many similar parts as desired can be connected one behind the other, so that an extensive programme of connections can be carried out in the same switch. 3 indicates in Fig. 1 the middle part, i. e. the actual casing of the switch containing a grooved mechanism, the connecting spring and the time spring.

In the same casing, but separately detachable, there is the clockwork mechanism 4, which can be operated in seconds, minutes or hours according to the cogwheel transmission. 5 indicates the switch knob; 6 the operating shaft; 8 shows the actual contact bridge, which connects or opens the contacts 7; 9 is the contact spring which is operated by the guiding part 10; 11 is, then, an opening for the operating shaft to come through (cf. Fig. 2).

In Fig. 3 number 18 indicates a cutout in the easing 3 in which the curled end 17 of the connecting spring 16 is held. Stop 14 of the driver 12, more clearly described below, is shown in the center of spring 16.

In Fig. 4 we see the toothed segment 34, which in the exemplified performance of the invention winds up the clockwork when turned right tightening spring 30.

Fig. 5a shows the driver 12, which has a cam at 13, limiting stops at 14 and at 15 a groove for the connecting spring 16. At 17 the connecting spring then fits into the casing.

The operation of the new cam actuated switch goes on as follows: When knob 40 with disc 39 will be turned clockwise the axle 41 and with it the toothed segment will be turned likewise and the clockwork spring will be tightened. That spring is suspended at 29 on the turning axle and at 33 on the switch casing. The toothed segment 30 operates onto a braking mechanism (not shown in the drawing) attached to the sheet billet 36 by means of a turnable pinion 38, which is pressed on by the spring 37. Simultaneously one of the radial end faces of the opening 19 in Fig. 6 will engage the lug 14 of the driver 12 of the pre-tightened connecting spring to move the cam 13, the sliding bolts 10, and hence the contacts 8 The winding-up movement is limited by a cog 35. After release of the handle the wound-up spring 30 will return the toothed segment 34 to its starting position whereby the toothed segment 34 engages the pinion 38, which in turn drives the braking mechanism (not shown) so that this return movement will proceed slowly. As the toothed segment 34 approaches its starting position, it will become disengaged from the pinion 38 and at the same time the other radial face of the cutout 19 will engage a radial face on the lug 14 of the driver 12 to move the driver 12 and the cams 13 thereon so that the sliding bolts 10 can return to their initial position.

When the knob 14 is turned anti-clockwise the driver 12 also will be moved in this direction, and according to the arrangement of the cams 13 one or several con tacts S will be operated. The movement of the driver 12 takes place again contrary to the springs 16 and 17. The time spring 30 with its ends 31 and 32 will be stopped in its action, since the end 31 is not directly attached to the axle 41, but to a lug 29 of the second driver 28, which can only be turned to its initial position, and when the switch is turned further anti-clockwise it cannot follow the turning movement. Still, in order to move the fixed part of Fig. c, the lugs 28 run into the openings at 27.

The single positions of the untimed system are operated by grooves 21 and 22 (Fig. 6) with the roll 23 (Fig. 4), which operates together with the stop springs 24 and 25, i. e. the guiding parts and 26.

The single drivers and stops correspond to one another, so that the time spring is inoperative in the intervaled positions and similarly it does not inhibit the switch spring during the operation of the time system.

In the diagram showing the torsional moments switch positions are indicated on the horizontal, starting with the zero position of the switch lever, to left and right; the clockwork on the right and the intervaled positions on the left.

On the positive co-ordinate the characteristics of the time spring are entered, lying on the stop at zero with a pre-tension of e. g. 2,000 cmg., and when turned e. g. 30", i. e. from the switching-on position of the clockwork working against the braking movement of the inhibiting mechanism.

On the negative side of the torsional moment the'connecting spring may lie e. g. at 25 on a stop, and it is seen that the crossbar, i. e. the operating shaft is springbound around zero due to the cooperation of the connecting and the time spring.

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one of its operating positions; first spring means mounted on said support member and normally urging said operating member in a first direction; second spring means normally urging said operating member in a second di- 2 rection difierent from said first direction; a time-de- The effect of the connecting spring is increasing with pendent switching mechanism mounted on said support member and co-operating With some of said cams when said operating member is moved in said first direction to be operated by the same; an additional switching mechanism mounted on'said support member and cooperating with some of said cams when said operating member is moved in said second direction to be operated by the same; a first stop member arranged on said support member against which said first spring means abuts when said operating member is moved in said second direction; and a second stop member arranged on said support member against which said second spring means abuts when said operating member is moved in said first direction.

References Cited in the file or" this patent UNITED STATES PATENTS 1,332,020 Andersen Feb. 24, 1920 1,384,533 Leake July 12, 1921 1,831,605 Porter May 10, 1931 1,916,485 Manrodt July 4, 1933 2,433,347 Deakin Dec. 30, 1947 2,603,725 Dietrich July 15, 1952

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