Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B43/00—Machines, pumps, or pumping installations having flexible working members
  • F04B43/12—Machines, pumps, or pumping installations having flexible working members having peristaltic action
  • F04B43/1253—Machines, pumps, or pumping installations having flexible working members having peristaltic action by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing

Definitions

• the invention relates to peristaltic pumps, in particular to a small pump for dispensing liquid detergent into a dish washing machine.
• Peristaltic pumps are well known in the prior art and may be defined as pumps which produce pulse-like contractions that propel matter along inside a tube.
• Fig. 1 there is shown a prior art device that was manufactured by Knight Equipment International, Inc., of Costa Mesa, California, now Knight, Inc. of Northbrook, Illinois.
• a pump 12 Inside a casing 10, there is a pump 12 in which a triangular rotor 14 rotates to compress a flexible rubber tube 16 against a curved wall 30 at points A and B. These points A and B change along the length of the tube 16 as the rotor 14 rotates around its central axis 18. Three pins 20 hold three rollers 22 at tips X, Y and Z of the rotor 14 while four screws 24 hold front and back portions of the casing 10 together.
• the tube 16 has an inlet suction branch 16C and an outlet delivery branch 16D. Arrows I and O indicate the direction of flow of liquid detergent into and out of the tube 16.
• a clear, hard plastic cover 26 with a tab 28 allows a user to view and to have access to the interior of the casing 10 in order to replace or repair any parts of the pump 12 and the rotor 14 which may break.
• the invention may be summarized as a small screwless peristaltic pump which is resistant to constant vibrations caused by a machine to which it is attached so that the pump does not become loose and fall apart.
• a primary object of the invention is to hold the pump together without screws when the pump is used in low torque and low vibration operations.
• a secondary object of the invention is to support a motor onto a rear casing portion of the housing.
• a tertiary object of the invention is to make the pump, its internal rollers and a flexible tube impervious to deleterious ingredients contained in liquid detergent.
• a key advantage of the present invention is that only a predetermined amount of the liquid detergent enters the pump because the synchronous motor, as controlled electronically, meters the detergent to prevent waste in the dish washing machine.
• Fig. 1 is a front elevational view of a known prior art device.
• Fig. 2 is an exploded front perspective view of a first embodiment of the invention.
• Fig. 3 is an exploded front perspective view of a rotor and rollers inside the first embodiment.
• Fig. 4 is a top end view of a front portion of a casing of the first embodiment.
• Fig. 5 is a front inside elevational view of a back portion of the casing of the first embodiment.
• Fig. 6 is an assembled perspective view of the first embodiment.
• Fig. 7 is an exploded rear perspective view of a second embodiment of the invention.
• Fig. 8 is an exploded front perspective view of a rotor and rollers inside the second embodiment.
• a small plastic peristaltic pump 112 contained in a main housing which has a front casing portion 100 and a cover or a rear casing portion 110.
• the front casing portion 100 and the rear casing portion 110 are snap-fitted together in a manner described below.
• a bracket 164 is formed integrally with a side of the front casing portion 100. This bracket 164 attaches the main housing containing the pump 112 to a dish washing machine (not shown).
• An electrical plug 174 allows alternating current to be carried through wires 176 from an activator (not shown) when it is switched on by a user who desires to wash a load of dishes.
• an inlet suction branch 106 Upon activation, an inlet suction branch 106 brings a predetermined amount of liquid detergent flowing from a reservoir (not shown) in a direction I into a flexible rubber U-shaped tube 116 held in place at an inlet to the pump 112 by a U-shaped inlet channel 104 integrally formed on a top surface of the front casing portion 100.
• a U-shaped inlet channel 104 integrally formed on a top surface of the front casing portion 100.
• the rollers 122 compress the flexible tube 116 at equally spaced intervals against an interior side of a curved wall 130.
• rollers 122 are shown, a manufacturer may choose to use more or less rollers, for example, four or two rollers instead. Nevertheless, three rollers 122 are preferred.
• the rollers 122 are rolled along the flexible tube 116 as they are rotated by the rotor 114 which is turned by an output shaft 118 extending from a synchronous gear motor 132.
• Ears 166 project from opposite sides of the motor 132.
• Bosses 142 on an outer periphery of the front casing portion 100 extend through hollow cylindrical sleeves 144 into upper and lower holes in the ears 166 and are ultrasonically heated until they melt to spot weld the motor 132 to the rear casing portion 110.
• a predetermined amount of the liquid detergent enters the pump 112 because the synchronous motor 132 meters the detergent to prevent waste in the dish washing machine.
• the amount of liquid is predetermined by the signal sent to the motor 132 which then turns its shaft 118 and the rotor 114 mounted thereon a predetermined number of times.
• the motor 132 is rated at 120 volts of alternating current (AC) at 60 hertz (Hz). The rated current is .05 amps and the rated speed is 20 revolutions per minute (rpm), plus or minus 10%.
• Pulse-like contractions are produced inside the flexible tube 116. These contractions propel the liquid detergent in spurts along the inside of the flexible tube 116 held in place at an outlet from the pump 112 by a U-shaped outlet channel 108 until the liquid detergent is dispensed by being squirted out of an outlet delivery branch 160 in a direction O into the dish washing machine (not shown).
• the U-shaped outlet channel 108 is formed integrally on a top surface of the front casing portion 100.
• the pump 112 in Fig. 2 is secured together against the constant vibrations of the dish washing machine by three types of plastic devices for snap-fitting the front casing portion 100 together with the cover or rear casing portion 110.
• the first type is a C-shaped groove (not shown) in a circular recess 135 into which a C-shaped tongue 136 is inserted. In an alternate embodiment, at least a pair of straight grooves and a mating pair of straight tongues 136 may be used.
• the second type of plastic device is a trio of square, open-ended boxes 138 into which a trio of springy, plastic clip pairs 140 are inserted.
• the third type of plastic device is the pair of bosses 142 on each side of the front casing portion 100.
• the bosses 142 are inserted through the pair of hollow cylindrical sleeves 144.
• only one boss 142 and one sleeve 144 may be used. Note that the groove in the recess 135, the boxes 138 and the bosses 142 are positioned on an outer periphery of the front casing portion 100 while the tongue 136, the clip pairs 140 and the sleeves 144 are positioned on an outer periphery of an interior wall of the rear casing portion 110.
• the groove in the recess 135, the boxes 138 and the bosses 142 may be positioned on the rear casing portion 110 while the tongue 136, the clip pairs 140 and the sleeves 144 may be positioned on the front casing portion 100.
• An ultrasonic welding rod (not shown) is applied to three areas on an exterior wall of the rear casing portion 110 where the bosses 142 are inserted through the sleeves 144 into the ears 166 in order to heat and melt each boss 142 into its aligned sleeve 144 and ear 166 so that the boss 142, the sleeve 144 and the ear 166 are fused together.
• the pump 112 is not jarred apart by the constant vibrations caused by the dish washing machine. hi Fig.
• the triangular rotor 114 for low torque and low vibration operations is illustrated.
• the rotor 114 and its rollers 122 are exploded apart to show how they are connected together.
• a front face 146 of the rotor 114 has formed integrally on its inner side three stepped male inserts 148.
• a rear face 150 has formed integrally on its inner side three aligned cylindrical barrels 152 with which the male inserts 148 mate.
• Each roller 122 has a cylindrical bore 156 through its center along its longitudinal axis 158.
• a dowel 154 is mounted inside the rotor 114 and aligns the plurality of mated inserts 148 and barrels 152 around a central D-shaped bore 172.
• a single central large cylindrical barrel 170 carries the dowel 154 and surrounds the D-shaped bore 172 through which the shaft 118 of Fig. 2 with its D-shaped cross section passes in order to rotate the rotor 114.
• the rotor 114 is assembled in the following manner. First, the rollers 122 are slipped onto the barrels 152. Second, the inserts 148 are plugged into the bores 156 of the barrels 152 so that the mated inserts 148 and the barrels 152 carry the rollers 122. Simultaneously, the dowel 154 is inserted into a bore (not shown) made in the inner side of the front face 146.
• An ultrasonic welding rod (not shown) is applied to three areas on an outer side of the rear face 150 where the inserts 148 are plugged into the barrels 152 so that the inserts 148 and the barrels 152 are fused together.
• care must be taken so that too much heat is not applied in order to prevent the rollers 122 on the barrels 152 from being deformed.
• Fig. 4 there is shown a top end view of the front casing portion 100 which functions as part of the main housing for both the first and second embodiments.
• the U- shaped inlet channel 104 secures an entrance for the flexible tube (not shown) while the U- shaped outlet channel 108 secures an exit for the flexible tube.
• a top of one box 138 is also seen.
• a pair of bosses 142 on each side, of which only the top boss 142 is seen, is insertable through the pair of hollow cylindrical sleeves 144 on each side shown in Fig. 5 on the interior wall of the rear casing portion 110.
• the bracket 164 attaches the front casing portion 100 to the dish washing machine (not shown).
• the front casing portion 100 is also secured to the rear casing portion 110 of Fig. 5 by the trio of clip pairs 140 which are inserted into the boxes 138 of Fig. 4, of which only one box 138 is shown in Fig. 4.
• the circular tongue 136 arranged on the interior wall of the rear casing portion 110 is inserted into the groove (not shown in Fig. 4, but see the back of the groove in the recess 135 illustrated in Fig. 2).
• Li Fig. 5, an opening 162 through the center of the rear casing portion 110 allows the output shaft 118 seen in Fig. 2 to extend therethrough to engage with and drive the rotor 114 of Fig. 3.
• the pump 112 is shown to be assembled with the motor 132.
• the operation of the pump 112 and the motor 132 in this first embodiment may be understood by following the path of movement of the liquid therethrough.
• the liquid maybe other than a detergent.
• the motor 132 is turned on when it receives a signal through the wires 176 of the plug 174 to meter the flow of liquid in the direction I into the inlet suction branch 106 which leads to the flexible tube 116 that is held securely by the U- shaped inlet channel 104.
• the signal energizes the motor 132 to turn its shaft 118 seen in Fig.
• Fig. 2 there are no screws holding the pump 112 together with its housing which includes the front casing portion 100 and the rear casing portion 110. Also, in this first embodiment for low torque and low vibration operations, there are no screws supporting the motor 132 onto the exterior wall of the rear casing portion 110. Note further that the pump 112, the rollers 122 and the tube 116 are all impervious to deleterious ingredients contained in the liquid detergent. In Fig. 7, the second embodiment for high torque and high vibration operations is illustrated.
• the pump 112 is contained in the main housing which has the front casing portion 100 and the cover or rear casing portion 110.
• the front casing portion 100 and the rear casing portion 110 are snap-fitted together in the manner described below.
• the bracket 164 is formed integrally with a side of the front casing portion 100 and attaches the main housing containing the pump 112 to the dish washing machine (not shown).
• the electrical plug 174 allows alternating current to be carried through the wires 176 from the activator (not shown) when it is switched on by a user.
• the inlet suction branch 106 brings a predetermined amount of liquid detergent flowing from a reservoir (not shown) in the direction I into the flexible tube 116 held in place at the inlet to the pump 112 by the U-shaped channel 104 integrally formed on the top surface of the front casing portion 100.
• rollers 122 Inside the pump 112, there is a plurality of rollers 122 on tips X, Y and Z of the rotor 114 confined between the front casing portion 100 and the rear casing portion 110.
• the rollers 122 compress the flexible tube 116 at equally spaced intervals against the interior side of the curved wall 130.
• the rollers 122 are rolled along the flexible tube 116 as they are rotated by the rotor 114 which is turned by the output shaft 118 (not shown but see Fig. 2) extending from the motor 132.
• Screws 168 are inserted into upper holes in the ears 166, extend through the upper sleeves 144 on the rear casing portion 110 and pass through bores 178 in the front casing portion 100 where the screws 168 are secured at their ends by bolts 182 of which only one is shown.
• the bosses 142 extend from the front casing portion 100 through the lower sleeves 144 into the lower holes in the ears 166 and are ultrasonically heated until they melt to spot weld the motor 132 to the rear casing portion 110.
• the screws 168 may be inserted into the lower holes in the ears 166 and the bosses 142 may be extended through the upper holes in the ears 166 to achieve the same result. Note that this combination of screws 168 and bosses 142 is intended for high torque and high vibration operations.
• Pulse-like contractions are produced inside the flexible tube 116 as the rotor 114 rotates the rollers 122 along the curved wall 130 to compress the tube 116. These contractions propel the liquid detergent in spurts along the inside of the tube 116 which is held in place at the outlet from the pump 112 by the U-shaped channel 108 until the liquid detergent is dispensed by being squirted out of the delivery branch 160 in the direction O into the dish washing machine (not shown).
• the channel 108 is formed integrally on a top surface of the front casing portion 100.
• the pump 112 in Fig. 7 is secured together against the constant vibrations of the dish washing machine by three types of plastic devices for snap-fitting the front casing portion 100 together with the cover or rear casing portion 110.
• the first type is the C-shaped groove 134 into which the C-shaped tongue 136 is inserted.
• the tongue 136 is not shown in Fig. 7, but see Fig. 2.
• at least a pair of straight grooves 134 and a mating pair of straight tongues 136 may be used.
• the second type of plastic device is the trio of square boxes 138 into which a trio of springy clip pairs 140 are inserted. Only one pair of the clips 140 is seen in Fig. 7.
• the third type of plastic device is the pair of bosses 142, one on each side of the front casing portion 100.
• the bosses 142 are inserted through the lower sleeves 144 into the lower ears 166 on the motor 132.
• the groove 134, the boxes 138 and the bosses 142 are positioned on an outer periphery of the front casing portion 100 while the tongue 136 (not shown in Fig. 7 but see Fig. 2), the clip pairs 140 and the sleeves 144 are positioned on an outer periphery of an interior wall of the rear casing portion 110.
• the groove 134, the boxes 138 and the bosses 142 may be positioned on the rear casing portion while the tongue 136 of Fig. 2, the clip pairs 140 and the sleeves 144 may be positioned on the front casing portion 100.
• An ultrasonic welding rod (not shown) is applied to three areas on the exterior wall of the rear casing portion 110 where the bosses 142 are inserted through the lower sleeves 144 into the lower holes in the ears 166 in order to heat and melt each boss 142 into its aligned lower sleeve 144 and lower hole of the ear 166 so that the boss 142, the sleeve 144 and the ear 166 are fused together.
• the pump 112 is not jarred apart by the constant vibrations caused by the dish washing machine.
• skirt 180 at least partially surrounding the sleeves 144 on each side of the rear casing portion 110 to form a recessed area into which the ears 166 may fit so as to prevent wobbling of the motor 132 when it is activated.
• skirts 180 in the first embodiment for low torque and low vibration operations.
• the skirts 180 are not seen in the first embodiment because Fig. 2 is a front perspective view which hides the skirts 180.
• FIG. 8 the triangular rotor 114 for high torque and high vibration operations is illustrated.
• Three T-shaped supports 184 reinforce the rotor 114 against high torque and high vibrations, hi the first embodiment shown in Fig. 3 for low torque and low vibration operations, there are no T-shaped supports 184 reinforcing the rotor 114.
• Fig. 8 the rotor 114 and its rollers 122 are exploded apart to show how they are connected together.
• the front face 146 of the rotor 114 has formed integrally on its inner side three stepped male inserts 148.
• the rear face 150 has formed integrally on its inner side three aligned cylindrical barrels 152 with which the male inserts 148 mate.
• Each roller 122 has a cylindrical bore 156 through its center along its longitudinal axis 158.
• the dowel 154 is mounted inside the rotor 114 and aligns the plurality of mated inserts 148 and barrels 152 around the central D-shaped bore 172.
• the single central large cylindrical barrel 170 carries the dowel 154 and surrounds the D-shaped bore 172 through which the shaft 118 of Fig. 2 with its D-shaped cross section passes in order to rotate the rotor 114.
• the rotor 114 is assembled in the following manner. First, the rollers 122 are slipped onto the barrels 152. Second, the inserts 148 are plugged into the bores 156 of the barrels 152 so that the mated inserts 148 and the barrels 152 carry the rollers 122. Simultaneously, the dowel 154 is inserted into a bore (not shown) made in the inner side of the front face 146. The ultrasonic welding rod (not shown) is applied to three areas on the outer side of the rear face 150 where the inserts 148 are plugged into the barrels 152 so that the inserts 148 and the barrels 152 are fused together. However, care must be taken so that too much heat is not applied in order to prevent the rollers 122 on the barrels 152 from being deformed.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Reciprocating Pumps (AREA)
• Detail Structures Of Washing Machines And Dryers (AREA)

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• 2005
  • 2005-08-05 US US11/197,381 patent/US20070031272A1/en not_active Abandoned
• 2006
  • 2006-07-28 WO PCT/US2006/029227 patent/WO2007019071A2/en active Application Filing
  • 2006-08-04 TW TW095128757A patent/TWI484098B/zh active

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