US2980393A - Pneumatic timer - Google Patents

Description

April 18, 196 c. c. BAUERLEIN PNEUMATIC TIMER 2 Sheets-Sheet. 1

Filed May 7, 1958 FIG. 3

'III/IIIIIIIIII/IIIII INVENTOR. CARL c BAUEIZLEI M FIG. 1

April 18, 1961 c. c. BAUERLEIN PNEUMATIC TIMER 2 Sheets-Sheet 2 Filed May 7, 1958 INVENTOR. CARL. C. BAUEZLEN 'ATTOZMEYS wd W% Unite States PNEUMATIC TIMER Filed May 7, 1958, Ser. N 733,649

4 Claims. (Cl. 251-262) This invention relates to improvements in timers for controlling the carrying out of a series of sequential operations, and more particularly relates to a pneumatic timer particularly adapted to carry out the cyclic washing, rinsing and extracting operations of an automatic washing machine and the like.

A principal object of the invention is to provide a new and improved timer for controlling the carrying out of a series of fluid pressure operations and con structed with a view towards utmost simplicity in construction and efliciency in operation.

A further object of the invention is to provide a pneumatic timer having a series of timer valves therein, in which the valves are self-closing and are maintained in operative engagement with the timer cams by inlet pressure on the valves.

Another object of the invention is to provide a simplified form of cam operated self-returning pneumatic valve for pneumatic timers and the like, in which the valve chamber is closed by a diaphragm connected with the valve, and in which inlet air enters the chamber between the valve and diaphragm and biases the valve into a closed position and into engagement with the operating cam therefor.

A still further object of the invention is to provide a simplified and improved form of timer for controlling a series of pneumatic operations, in which the timer consists in a valve block having a plurality of open ended valve chambers therein, wherein one end of the chambers is closed by a single diaphragm and wherein the diaphragm has a series of valves formed integrally therewith having wiping engagement with the wall of the chamber, and of a lesser eflective area subjected to air under pressure than the effective area of the diaphragms, and thereby biasing the valves in their closed positions and into engagement with the operating timer cams therefor by pressure on the diaphragms.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings wherem:

Figure l is a plan view of a timer constructed in accordance with the invention;

Figure 2 is a fragmentary sectional view of the timer shown in Figure 1, taken substantially along line 11-11 of Figure 1;

Figure 3 is an end view of the timer; and p p Figure 4 is a fragmentary detail vertical sectional view taken along the inlet to the valve block in order to show the fluid passageways to the valve chambers.

In the embodiment of the invention illustrated in the drawings, I have shown a timer of a type particularly adapted for pneumatic control systems for washing machines and the like, for carrying out the cyclic washing, rinsing and extracting operations of the machine.

The timer 10 includes a valve block 11 having a plurality of open ended valve chambers 12 therein opening to 2,980,393 Patented Apr. 18, 1951 opposite faces of the valve block. An inlet fitting 13 extends from one end of the valve block and has an inlet passageway 14 therein, leading into the valve block and having communication with an enlarged diameter passageway 15 extending at right angles to the inlet passageway 14 and opening to one face of the valve block 11, herein shown as being the top thereof. The passageway 15 is shown as having communication With-a groove 16 extending along the valve block for a portion of the length thereof and around a central outer boss 17, forming a mounting for a timer shaft 19. Inlet grooves 20 opening to the top of the valve block lead from the groove or passageway 16, and have communication with enlarged diameter portions 21 of the valve chambers 12. The grooves 16 and 20 are herein shown as being sealed by a diaphragm 23 extending along the top of the valve block and sealed thereto as by a cover plate 24.

Outlet passageways 25 are shown as leading from reduced diameter wall portions 26 of the valve chambers 12. The outlet passageways 25 lead through projections or fittings 27 projecting outwardly from the side walls of the valve block, and from the end wall of the block, opposite the inlet projection 13. The fittings or projections 27 are adapted to form fittings for conduits (not shown), connected to certain fluid operated motors (not shown) for eflecting the carrying out of the cyclic operations of a washing machine and the like.

The diaphragm 23 may be molded from rubber, or from one of the well known substitutes for rubber, such as an elastomer and the like, and as herein shown has flexible bellows-like diaphragm portions 30 extending over the valve chambers 12 and sealed to the top of the valve block 11 by the cover 24, secured to said valve block in a suitable manne The diaphragm 23 also has integrally formed thickened portions or stems 31 extending inwardly from the bellows-like portions 30 within the valve chambers 12, and having flared. flexible valves 33 formed integrally therewith and having wiping engagement with the reduced diameter portions 26 of the valve chamber 12.

Each valve 33 is herein shown as being molded integrally with the diaphragm portion 23 and stem 31, and has a generally frusto-conical valve face 35 having a recessed innerside 36, facing the diaphragm portion 30 and providing resiliency in the valve, so as to accommodate inlet pressure to force the valve face into wiping engagement with the wall of the valve chamber 12.

An operator 39 is shown as extending along the valve and stem 31, and may be molded to said valve and stem. The operator 39 has an enlarged diameter portion 40, extending outwardly from the diaphragm portion 30 through the top of the cover 24. A rounded outer end portion '41 of said operator forms a follower engageable with a cam 43 on the undersurface of a dial knob .44 rotatably driven by a timer motor 45.

The cover 24 has outwardly extending cap portions 46 encircling each diaphragm portion 30, and extending outwardly therefrom to afiord movement of the bellows-like diaphragm portions 30 outwardly of the valve block 11 as the valves are moved to their closed position.

It should here be understood that the diaphragm portions 30 are so molded as to normally bias the valves 33 to the closed positions shown, which in Figure 2 are the valves on the left-hand side of the valve block. Inlet air under pressure enters the enlarged diameter portions 21 of the valve chambers 12 through the passageways 20 in the space between the valves 33 and the underside of the bellows-like diaphragm portions 30, and is sealed to the valve chamber 12, by the valves 33 and diaphragm portions 30, when the valves are in their closed positions.

It will further be noted that the eflective area of the bellows-like diaphragm portion 30 subjected to air at inlet pressure is larger than the effective area of the por- 1 tion of the valve'33 facing the underside of the diaphragm portion 39." The differential in pressure on said diapbragm portion and valve will, therefore, bias thevalve .33Fin a closed position and'will .bijas 'thciollower end port on ,41 of the operator 39..in1torcngagemientwith it cam 43, th us obviating the need for a return spr ng for the valve and a biasing spring for the :follower end portion of the operator for the valve. r

; As shown in igur L slee e ei env lue Opening s formed e nrqpsmn itoztb 12 one;

portion 50 of the dial knob 44, and forming a-lslot' to receivea hairpin spring clip 53, morrnteditherein, The hairpin spring clip 53 forms a spaced recesses 55 in the timer shaft 19,;and forming in eifect detent recesses, indexing the dial knob 44' in its inwardly extendingv on position and in its outwardly eitchding-o position.

'Thus, when the dial knob 44 is moved outwardly along the timer shaft 1'9, to engage the spring clip 53 with the outer recess 55 in the timer shaft 19, the timer will be in its position and the timer cams 43 will be ineffective to. operate the valve 33. When,'however, the dial knob-44. is pressed inwardly along the timer shaft 19 to engage the spring clip 53 with the inner recess 55, the timer cams 43 will be in position to operatethe valves 33 in the required sequence. 'The under face of therecessed portion 50 of the dial knob 44 will also come into engagement with abutton 56 ofa limit switch 57, to depress, said button and complete an energizing circuit to the timer motor 45, to energize said timer motor.

The limit switch 57 may be of any well known form-, and is shown in Figure 1 as being suitably mounted on the top of the cover 24 between two inner valve chambers 12, to be engaged by the undersurface of the dial knob 44,, to efiect closing of the circuit to the timer motor 45, when the dial knob 44 is depressed, and openiug of the circuit when the dial knob '44'is moved outwardly position to register the spring clip 53 with the outer recessed portion 55 of the timer shaft 19. It should here be understood that when the timer is 7 used to control the sequential operationsof a washing machine or the like, that the. energizing circuit to the limit switch 57 may be controlled through a suitable water level control (not shown), completing a circuit to ,tlielimit switch 57, when the level. of water in the washing machine tub (not shown) is at the required'level for. washing, and preventing operation of the timer before the tube has been filled to a selectedglevel.

,The timer motor 45 may be of any well known form,

V commonly used for driving timer cams, and as herein shown has a casing 59 formed as apartof the motor casingiand forming a housing for a speed reducer (not shown), asis common with timer motors ofthe class described, so .not .herein shown or described further. The speed reducer contained within the casing 59 in- 'cludes a ,shafttit) extending outwardlyfrom the housing 59 toward the. valveblock 11,1andhaving a pinion 61 mounted thereon and meshing \vithand driving a timer gear63'. The timer. gear 63 has a hub 64 extending within a 'boss- 65 extending outwardly from the valve block 11, and'is freely mounted-onthe timer shaft 19. A screw 66 threaded within the end of said timer shaft, and a' washer-67 0 said screw, abutting the outside of" the timer gear 63,'serves to retain the timer gear 63 to the m r ha t i 7 detent engageable with A one-way drive connecti n is provided between the timer gear 63 and the timer shaft 19, for driving said timer shaft in one direction only, Said one-way drive connection is herein shown as being in the form of a spring clutch 69. The spring clutch 69 may be of a well known form which wraps around the timer shaft 19, to drive the timer shaft when the timer gear 63 is driven in a driving direction, but to accommodate turning of the dial knob 44 and timer shaft 19 in a direction opposite to which the shaft and dial knob 44 are rotatably driven by thetimer motor 45.

. V valve block.

Spring clutches of the type herein shown are well known to those skilled in'the art and form no part of the present invention so need notlherein be shown or described further. j i

It may be seen from the foregoing that a simplified form of pneumatic timer has been provided, in which the timer valves are self-closing by the bias of the diaphragms therefor, and that the differential in'pressure acting on the diaphragms and the timervalves biases the valvesin their ,otf positions and biases the followers into engagement with the operating cams therefor.

It may further be seen that the construction of the timer is simplified by the useer a single. diaphragm ing the cam structure, and enabling the timer valves to be placed on opposite sides of the center'line of the Itiwill be understood that various modifications-and variations of the present invention may be effected without departing from the spirit and scope of the novel concepts thereof.

I claim as my invention: 7 v

.1. A self-returning pneumatic valve particularly adapted for pneumatic timers and the like, comprising a valve block having a valve chamber therein having a generally cylindrical wall, an inlet leading into said valve block and having communication with said valve chamber, adjacent one end thereof, an outlet leadingthrough the wall of said valve chamber in axially spaced relation with respect to saidinlet, a valve having a resilient flared valve face movable along the cylindrical wall of said valve chamber in sealing engagement therewith and aifording communication between said inlet'and said outlet, when saidvalve is in its open position, a yieldable diaphragm closing the end of said chamber adjacent said inlet and having connection with said valve, the facing surfaces of said valve and said diaphragm being subject to inlet pressure when said valve is in its open and closed positions,

from said valve chamber inaxially spaced relation with respect to said inlet, a valve havin'g'a resilient 'fla'red face movable along'the wall of said valve chamber in sealing engagement therewith and affording communication between said inlet'and said outlet, an operatorextending from said valve and diaphragm tothe outside of said valve block, an'operatingmembcr 'engageable with said operator and operative to move said valve to its open position to afiord communication between said inlet and said outlet, and the effective area of said diaphragm being greater than the effective area of said valve, and biasing said valve into a closed position by inlet pressure, and biasing said operator into engagement with said operating member.

3. A self-returning pneumatic valve particularly adapted for pneumatic timers and the like, comprising a valve block havin a valve chamber therein and opening to opposite sides of said valve block, an inlet leading into said valve block and having communication with said valve chamber adjacent one end thereof, an outlet leading from said valve chamber and valve block in axially spaced relation with respect to said inlet, a diaphragm sealed to said valve block and closing the end of said valve chamber adjacent said inlet, a valve Within said valve chamber-and spaced from said diaphragm and formed integrally therewith, said valve having a resilient flared face having sealing engagement with the wall of said chamber and biased into engagement with the Wall of said chamber by the pressure of fluid acting thereon, the facing surfaces of said diaphragm and valve being subjected to inlet pressure, and the efiective area of said diaphragm being greater than the effective area of said valve, to bias said valve into a closed position.

4. A self-returning pneumatic valve particularly adapted for pneumatic timers and the like, comprising a valve block having a valve chamber therein opening to opposite sides of said valve block and having a generally cylindrical wall, a flexible diaphragm closing one open 5 end of said valve chamber, an inlet leading into said valve block and having communication with the end of said valve chamber adjacent said diaphragm, an outlet leading from said valve chamber in axially spaced relation with respect to said inlet, a valve spaced from said diaphragm and formed integrally therewith and having a resilient flared valve face having sealing engagement with said cylindrical wall of said valve chamber and blocking the passage of air from said inlet to said outlet, when the valve is in a closed position, and accommodating the passage of air from said inlet to said outlet when said valve is in an open position, an operator extending from said valve and diaphragm, an operating member engageable with said operator for moving said valve into m open position upon rotatable movement of said cam, and the efiective areas of the facing surfaces of said diaphragm and said valve being such as to bias said valve into sealing engagement with the wall of said chamber and to bias said valve into a closed position and said operator into engagement with said operating member.

References Cited in the file of this patent UNITED STATES PATENTS 38,269 Osgood Apr. 21, 1863 852,802 Sears May 7, 1907 1,742,669 Ross Jan. 7, 1930 2,085,916 Marra July 6, 1937 2,391,718 Lindemann Dec. 25, 1945 2,510,465 Ellis June 6, 1950 2,798,124 Sharbaugh July 2, 1957

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