Diaphragm pressure switch adjusting mechanism for push buttons
I United States Patent 11 1 [111 3,875,359  
 Backus Apr. 1, 1975 DIAPHRAGM PRESSURE SWITCH nism comprises the pressure switch consisting of a dia- ADJUSTING MECHANISM FOR PUSH phragm which is connected to the bottom of the tub BUTTONS and which reacts to the pressure exerted by the water, i in accordance with the respective water level. When [76] Inventor wllilam Backus 363 Galahad&#34; the diaphragm reaches a certain predetermined Bolmgbrook 60439 height, it will interrupt the switch circuit and de-. [22] Filed: July 11, 1973 energize the water valve. This pressure switch can be adjusted b alternatin the ressure which has to be [2]] Appl&#39; 378372 exerted on the diaphra gm in order to reach the above Related U.S. Application Data described position. The pressure switch according to [63] Continuation-impart of Scr. No. 222.881 Feb. 2. this invention provides this adjustment in Such a way 1972 abandoned that the pin extending from the diaphragm is biased with the help of a pressure contact member which is 52 US. Cl. 200/83 5, 200/249, 200/328, pivotally mounted on the base of the main bracket of 337/319 the pressure switch adjusting mechanism. A tension [51] Int. Cl. HOlh 35/34 Spring Connects this P Contact with a Stepped 5 Fie|d f Search 200 3 WM, 3 S, 33 SA, lever which is mounted on the main bracket and 200/1 M 323 340 249; 337/319 3 0 3 1 which, when its position is changed, will change the tension of the spring. The position of this stepped le- 5 References Cited ver, in turn, is changed by a series of push buttons ar- UNITED STATES PATENTS ranged in a series of holes in support guides of the 741716! 3/1947 H 7/261 mam bracket in such a way that one step of the g W960 &#34;566 1 M stepped lever is positioned in the path of movement of Primary Examiner-B. Dobeck Assistant Examiner-Gerald P. Tolin Alrornav, Agent, or Firm-Teagno &amp; Toddy [57] ABSTRACT This invention provides a means for adjusting a pressure switch. for instance for obtaining various water levels in washing machines and the like. The mechasaid button shafts. The button shafts, when depressed. are held in place by a one-piece locking device which is pivotally mounted on the side edges of the bracket and which consist of an upper part, a lower part and a spring arm biasing it in the direction of the buttons, whereby a depressed button is released when another button is depressed.  
 5 Claims, 7 Drawing Figures DIAPHRAGM PRESSURE SWITCH ADJUSTING MECHANISM FOR PUSH BUTTONS CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of application Ser. No. 222,881, filed on Feb. 2, 1972 now abandoned.  
 BACKGROUND OF THE INVENTION This invention relates, in particular, to a mechanism for adjusting a pressure switch, in particular, a pressure switch to obtain various water levels in washing machines and the like.  
  It is often desired to wash various fabrics and/or various size loads of clothing in the same washing machine, and thereby to vary the amount of water placed in the tub of the washing machine.  
  The adjusting mechanisms which exist to regulate and control water levels in washing machines are complicated and expensive and have the tendency to become faulty and defective.  
  It is therefore the object of this invention to provide a simple mechanism which can be manufactured easily and which consists of few parts, which are practical and durable.  
 SUMMARY OF THE INVENTION This invention provides a pressure switch adjusting mechanism which is composed of few simple parts and which allows to determine the pressure exerted on a trip adjustment pin, connected to a diaphragm. This is effected with the help of a pressure contact member which is connected, via a tension spring, to a stepped lever whose position is changed with the help ofa pushbutton arrangement. Thereby, the change of position of the stepped lever changes the tension of the tension spring and thus the pressure exerted on the pin.  
  These and other objects, features and advantages of the present invention will be discussed in detail in the following description of the drawings, whereby variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure as specifically defined in the appended claims.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a front elevational view showing some parts in&#39; a section;  
  FIG. 2 shows a view corresponding to that of FIG. 1 whereby one of the buttons has been depressed and a maximum tension of the spring has been obtained;  
  FIG. 3 shows a side elevational view of the adjusting mechanism illustrated in FIG. 1;  
  FIG. 4 shows a sectional view generally taken along the line IVIV of FIG. 1;  
  FIG. 5 shows a sectional view of a button in the depressed position generally taken along line V-V of FIG. 4;  
  FIG. 6 shows a rear elevational view of the arrangement shown in FIG. 1; and  
  FIG. 7 shows a one-piece locking device comprising an upper part, a lower part and spring arm.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows an adjusting mechanism which is generally indicated at 10. It comprises a main bracket 12,  
 consisting of a horizontal support base 14 and support guides 16 and 18 which are parallel to the base 14. Both support guides have a series of holes formed therein, whereby the series of holes 20, 22, 24 and 26 in the upper support guide 16 corresponds to the series of holes 30, 32, 34 and 36 in the lower support guide 18.  
  A series of button shafts 40, 42, 44 and 46 are placed through the corresponding series of holes in the support guides 16 and 18. As shown in FIG. 1, these button shafts are hollow and have coil springs 50, 52, 54 and 56 mounted in their upper portions to maintain the button shafts in their raised position, when they have not been depressed. or return them to their raised position after they have been released from their depressed position. Each button comprises outwardly extending spring fingers 58 maintaining the button in the respective hole of the series of holes in the lower support guide 18, as well as outwardly extending nibs 60 which maintain a depressed button in its depressed position.  
  A locking device 64 is pivotally mounted on the main bracket at the points 66, 67 and 68 and it consists of an upper portion 70 serving to lock the buttons with the help of the mentioned outwardly extending nibs 60, a lower portion 72 and a spring arm 74. A button shaft is thereby released when another button shaft is de-&#39; pressed whereby the outwardly extending nibs 60 of the latter button rock the locking device 64. The locking device 64 is mounted on side hinge members 76 and 78, which are shown in FIGS. 3 and 5 and which form an integral part of the main bracket 12. The spring arm 74 biases the upper and lower portions 70 and 72 of the locking device in a direction towards the button shafts, and thus allows to secure the button shafts, when depressed, as shown in FIG. 2.  
  As illustrated particularly in FIGS. 1 and 2, a stepped lever 80 is pivotally mounted on the main bracket at hinge members 82 and 84 shown&#39; in FIG. 6. This stepped lever 80 is arranged in such a way that each of its steps 90, 92, 94 and 96 is positioned in the path of movement of one of the button shafts in such a way that a button shaft, when depressed, will contact the corresponding step of this stepped lever 80. This lever may consist of a flat piece of metal which is bent as shown in FIGS. 3 and 5, whereby the stepped portion 98 is bent at a substantially right angle from the mounting portion 100. The stepped portion gradually decreases from left to right, and a spring mounting arm 102 extends from the right end of this stepped lever in a direction opposite from that of the mounting-hinge arm 84 of the lever 80.  
  The spring 104 is connected to this spring mounting arm 102, in one of several notches 106 provided therein. The other end of this spring 104 is connected to a pressure contact member 108.  
  As shown in FIGS. 1, 2 and 4, the base portion of the main bracket comprises outwardly bent portions 110, 1 1 1, and 112, whereby the portions 111 and 112 serve to mount the pressure contact member 108 at mounting points 115 and 116 and the portion 110 comprises a stop 113 preventing the pressure contact member from being pushedv from its position. A trip adjustment pin 117 extends through a hole 118 in the base 14 and contacts the pressure contact member 108 at a raised portion 119 of this pressure contact member.  
  This pin 117 belongs to a diaphragm arrangement comprising a diaphragm 120 contained within a housing 122 which is connected with the bottom of the washing machine tub, via a flow port 124. When diaphragm 120 moves upwardly, it-will move the pin 117 with it, and whenthe pin 117 has reached a predetermined position, it willinterrupt the contact 126 which. in turn. will stop the flow of water into the tub.  
  The resistance of diaphragm I to the water entering into flow port 124 will be determined by the pressure contact member 108, which is processed via the pin 117, and the pressure on the pressure contact member 108, in turn, is determined by the pressure exerted by tension spring 104.  
  In addition, a mechanism for preadjusting the spring tension is provided at hinge 82 in the form of a screw adjusting mechanism 128. This will allow a fine adjustment by moving the stepped lever 80 in a direction perpendicular to that of the button shaft 40. Another means of preadjusting the spring tension is given by the notches 106 in such a way that the spring is mounted in any desired one of these notches.  
  in assembling the present adjustment mechanism, the locking device is slid through the open side of the bracket 12 and into the two pivotal mounting points 66 and 67 on the side edges of the bracket. Thereby, the spring arm is retained by a tap 130, which is bent away from hinge part 78. The locking device 64 is then held against the back of the main bracket 12, and the button shafts 40, 42, 44 and 46., containing the coil springs 50, 52, 54 and 56, are then inserted into the corresponding holes 20, 22, 24 and 26 of the main bracket 12. The  
 placement of the button shafts in their respective positions will prevent the locking device from leaving its position. The stepped lever 80 and the pressure contact member 108 are simply inserted into their respective hinges, and they are prevented from leaving their as signed positions by the application of the tension spring 104.  
  It will be apparent from the above description of the preferred embodiment that a simplified, practical and effective mechanism for adjusting a pressure switch has been provided by the present invention and, although there may be variations and modifications made by those skilled in the art, it is my desire to include these variations and modifications within the scope of my invention as defined in the appended claims.  
 I claim as my invention:  
  1. A push button mechanism for adjusting the pressure required to trip a switch in response to movement of a pressure diaphragm. said push botton mechanism comprising:  
 a. a main bracket assembly including a base and at least one support guide substantially parallel to said base, said support guide defining a plurality of openings;  
 b. a plurality of push button shaft means, each of said shaft means extending through one of said plurality of openings and having a normal, raised position and a depressed position;  
 c. a locking member pivotably mounted about a longitudinal axis and removably engaging each of said plurality of push button shaft means when each is in said depressed position and holding each in said depressed position and releasing the remainder of said plurality of push button shaft means, allowing each to return to said raised position;  
 d. a lever member having an end thereof pivotally mounted with respect to said main bracket assembly and defining a plurality of stepped areas, each of said stepped areas contacting a corresponding one of said plurality of push button shaft means when said one of said shaft means is in said depressed position;  
 e. pressure contact means operably connected to the pressure diaphragm;  
 f. biasing means operably connected to said pressure contact means and said lever member at an end of said lever member oppositely disposed from said pivotally mounted end to exert a biasing force on the pressure diaphragm, said biasing means being subjected&#39;to a preload, said preload being determined by the relative position of said lever member to said main bracket assembly, said lever member assuming a different relative position when each of said plurality of stepped areas is contacted by said corresponding push button shaft means in its depressed position; and  
 2. said lever member including means for mounting one end of said biasing means thereto, said mounting means comprising a plurality of connection points providing a coarse adjustment of said preload.  
  2. A push button mechanism as defined in claim 1 wherein said locking member has an upper portion, a lower portion and a spring arm, and said upper portion contacts said push button shaft means and secures them in said depressed position.  
  3. A push button mechanism as defined in claim 2 wherein depression of one of said plurality of push button shaft means rotates said locking member to release any previously depressed and locked push button shaft means.  
  4. A push button mechanism as defined in claim 1 wherein said preload on said biasing means is preadjustable by axial movement of said lever member.  
  5. A push button mechanism as defined in claim 4 further comprising a screw adjustment mechanism operable to provide axial movement of said lever mem- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. ,3 9 Dated April 1, 1975 Inventor(s) William H. Backus It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:  
 Col. 3, line 49: &#34;botton should read ---button-.  
 Col. 3 &amp; 4,claim l: Paragraphs (b) (c) and (d) are incorrect as printed and should read as follows:  
 (b) a plurality of push button shaft means, each of said shaft means adapted to extend through one of said plurality of openings and having a normal, raised position and a depressed position;  
 (c) a locking nanber mun-ted for rotation about a longitudinal axis and being operable to removably engage each of said plurality of push button shaft means when each is in said depressed position and to hold each in said depressed position and to release the of said plurality of push button shaft means to return to said raised position;  
  (d) a lever member having. an end thereof pivotally mounted with -respect to. said main bracket assanbly and defining a plurality of stepped areas, of said step areas being disposed to contact a corres- I I ponding one of said plurality of push button shaft means when said one of said shaft means is in said depressed position;  
 Signed and Emalcd this eighteenth Day Of N0vember1975 [S-E AL I A nest:  
 RUTH C. MASON C MARSHALL DANN :HHXIIHX ()f /m&#39;r (&#39;umnu&#39;ssium&#39;r n] Iurvnls am] Trademarks FORM PO-IOSO (10-69) USCOMM-DC 60376-P69 U.S GOVERNMENT PRlNTING OFFICE: a 9 Q3 0