GB1569950A

GB1569950A - Steam-pressure cooker

Info

Publication number: GB1569950A
Application number: GB582677A
Authority: GB
Original assignee: Braun and Kemmler GmbH and Co KG
Current assignee: Braun and Kemmler GmbH and Co KG
Priority date: 1976-03-06
Filing date: 1977-02-11
Publication date: 1980-06-25
Also published as: IT1073287B; DE2609302A1; BE852087A; JPS54123373A; FR2342693B3; FR2342693A1; NL7701603A; DE2609302C2

Description

(54) STEAM-PRESSURE COOKER (71) We, BRAUN & KEMMLER, of 7411 Reutlingen-Betzingen, German Federal Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a steam-pressure cooker.

For steam-pressure cookers for domestic use there exist technical safety conditions which prescribe a pressure limitation mechanism and a safety device, in which connection an optical and/or acoustic indication of the cooker operating pressure has to be given, a pressure increase above a specific limiting value has to be prevented and a safety device which acts separately from the devices described above is prescribed which prevents the lid of the pressure cooker from being opened so long as an excess pressure is still present in the cooker.

An object of the present invention is to combine all of the safety and indication devices of a steam-pressure cooker in one structural unit which works in an operationally reliable manner and gives rise to a simple mounting on the lid.

With this object in view the present invention provides a steam pressure cooker comprising a body portion and a lid with a handle, the lid and body being adapted for bayonet fastening one with another, the handle having a steam pressure limiting valve, a signal whistle mechanism, and an adjusting member mounted for rotation into a plurality of operative positions, the pressure limiting valve having an insert body adapted for insertion into a recess of the lid handle and arranged to provide a displaceable abutment for a loading spring of a closure member of the valve, the insertion position of the insert body being determined by the position of a slide mounted in the lid handle, the adjusting member being operative to displace the slide and to actuate a safety device whereby the lid is either locked in position on the cooker body or a sealing ring of the cooker is displaced to vent the interior of the cooker.

Through the common adjusting member, a simple and also reliable adjustment of the safety device is guaranteed. The arrangement of the safety device in the handle of the lid gives rise to the advantage that only the lid handle requires special shaping, while the associated handle of the cooker body and lid edges do not require any special provisions.

The adjusting member can advantageously act with two cams or eccentrics on the slide, one of which controls the position of the slide in its longitudinal displacement direction and the other of which controls a swivel position of the slide to affect the slide-in position of the insert body of the combined valve arrangement. In this respect the slide can advantageously be bifurcated at one end, engage into lateral slots on both side of the insert body and is displaceable by means of the common adjusting member into and out of engagement with the insert body.

The adjusting member is advantageously connected in a mechanically reliable manner to all of the parts, to be adjusted, via the eccentrics and the slide, coupling via springs which could become fatigued being thus avoided. In fact, in a preferred embodiment of the pressure cooker only two springs are employed, these being restoring springs for the valve closure member and for an indicator piston which is mounted in the closure member of the valve, the indicator piston being connected to and indicator rod protruding from the insert body.

The pressure cooker designed in accordance with the invention has, compared with known pressure cookers, the further advantage that a position alteration of the common adjusting member in operation is indicated acoustically, so that at all times a check for a desired position of the adjusting member is afforded.

In a preferred embodiment the acoustic signal indication does not consist of a permanent whistle, but the whistle signal occurs in each case only for a short time and is repeated after an interval of time. This is achieved in accordance with the preferred embodiment by virtue of the insert body defining first and second steam passage chambers in the handle, the chambers having respective steam outlet channels fashioned in the lid handle and being connected together by a narrow communication channel, the first steam passage chamber forming a steam damming space whose steam outlet channel is partially closed in a specific slide-in position of the insert body, and the second steam passage chamber forming a signal whistle chamber.

The valve can be dismantled for cleaning only with the lid removed. To this end the common adjusting member is so blocked by a blocking slide that it can be rotated into a main "Clean" position only with the lid removed.

An embodiment of a steam-pressure cooker of the invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a longitudinal section through a part of the lid handle of a pressure cooker in accordance with the invention with the adjusting member in the main position "Clean"; Figure 2 is a section through the adjusting member and safety device taken along the line II-II in Figure 1 with a schematic representation of the position of four eccentrics of the adjusting member, in the main position "Clean"; Figure 3 is a longitudinal section, corresponding to Figure 1, through the adjusting member and safety device with the adjusting member in a main position "Venting"; Figure 4 is a schematic representation of the eccentric position of the adjusting member in the main position "Venting";; Figure 5 is a sectional representation, corresponding to Figure 1, with the adjusting member in a main position "Weak"; Figure 6 is a cross-section, corresponding to Figure 2, through the adjusting member and safety device, with the adjusting member in the main position "Weak", the eccentric position of the common adjusting member being shown schematically; Figure 7 is a sectional representation, corresponding to Figure 1, but with the adjusting member in a main position "Strong"; Figure 8 is a schematic representation of the eccentric position of the adjusting member in the main position "Strong"; Figure 9 is a representation of the blocking slide in the sectional plane IX-IX in Figure 1 in the main position "Clean"; and Figure 10 is a representation, corresponding to Figure 9, of the blocking slide in other main positions, The sectional views in accordance with Figures 1, 3, 5 and 7 show, of the steam-pressure cooker, only a part of the lid 10 with the lid edge 11 and the sealing ring 12 inserted into the lid edge, as well as the upper edge region of the cooker body 13 with an edge part 14 bent out to provide for the bayonet union. Of the lid handle, from the sectional views only the metal housing 15 for the valve and adjusting member is evident, but not the actual handgrip part which is connected to the right thereof and which is formed from a poor heat-conducting plastics material. Also the body handle is not shown.

The housing 15 has two recesses 16 and 17 which are accessible from above and which are interconnected by a slot-like transverse channel 18 of the housing 15. From the front recess 16, two steam outlet channels 19 and 20 which widen outwardly and which are arranged one above the other lead to the end face 21 of the housing 15. In the base region of the recess 16, above a passage aperture 22, a valve seat 23 for a closure member 24 is fashioned. The passage aperture 22 is surrounded by an annular collar 25 which protrudes from the underside of the housing 15 and which has an external screw thread and which projects through an aperture in the lid. The fastening of the housing 15 to the lid 10 is effected along with interposition of a seal (not shown) by means of an annular nut 26 which is screwed onto the collar 25 and which butts against the inside of the lid 10.

Inserted into the recess 17 is a common adjusting member 27 which has a knob 28 resting on the upper side of the housing 15 and a cam shaft 29 extending into the recess 17. The adjusting member 27 is protected against axial displacement by a securing needle 56 which, upon insertion of the adjusting member 27, snaps into an annular groove 57 of the housing 15. Formed on the cam shaft 29 are four eccentrics 30,31, 32 and 52. A further adjusting cam 34 is formed on the inside of the bearing body 33 of the knob 28.

The eccentric 30 and the cam 34 of the common adjusting member 27 act on a slide 35 which is arranged in the slot-shaped transverse channel 18. The eccentric 31 acts on a venting bolt 36, while the eccentric 32 controls a locking bolt 37. The eccentric 52 controls a blocking slide 53, most evident from Figure 9 and 10, having a blocking nose 54.

The valve arrangement accommodated in the recess 16 will now be described with reference to Figure 3, in order not to overload Figure 1 with reference numerals. Inserted from above into the recess 16 is an insert body 38 which has two recesses 39 and 40 which form, in the recess 16 of the housing 15, two steam passage chambers. The inner steam passage chamber 40 communicates via an aperture 41 (Figure 5), closable by the closure member 24, with the region of the valve seat 23 and the subse quent passage aperture 22, leading towards the inside of the lid, of the housing 15.A connec tion of the inner steam passage chamber 40 to the steam outlet channel 19 is afforded via a connection channel 42 which leads to the upper steam passage chamber 39, but the steam out let channel 19 is closed, in a specific slide-in position of the insert body 38, by a web part 43 of the insert body 38.

The upper steam passage chamber 39 forms, together with the steam outlet channel 20, the signal whistle of the combined valve arrangement.

The valve arrangement consists of the already-mentioned closure member 24 which is mounted so as to be displaceable in the hous ing 15 and which is held by means of a compression spring 44 against the valve seat 23.

The compression spring 44 is supported with one end against the closure member 24 and with its other end against the insert body 38. In the closure member 24, a concentric indicator piston 45 is mounted so as to be longitudinally displaceable against the force of a compression spring 46 which is supported by the insert body 38. The indicator piston 45 is provided with an indicator rod 47 which pro trudes through an aperture from the insert body 38 and with a piston shaft 48 which projects into the interior of the lid 10.

From the sectional views of Figures 2 and 6 it is evident that the slide 35 is bifurcated at one end to form two tines 35a and 35b which can engage into lateral slots 50 and 51 of the insert body 38 and thereby secure the insert body 38 in its slide-in position.

Figures 1,3,5 and 7 show four different main positions of the safety device, which are given by different positions of the common adjusting member 27. Figures 2,4, 6 and 8 show the position of the four eccentrics 30, 31,32 and 52 of the common adjusting member 27 in the different main positions. A suitably arranged stop 49 which is indicated in Figures 2, 4, 6 and 8, prevents the adjusting member 27 from being rotated right round.

The stop 49 prevents a direct adjustment from the position "Strong" to the position "Clean".

Figure 1 shows the safety device in the main position "Clean", in which setting of the common adjusting member 27 the four eccentrics 30-32, 52 assume the position evident from Figure 2 and the slide 35, controlled by the eccentric 30, is withdrawn (Figure 2) with its two tines 35a and 35b out of the lateral slots 50 and 51 of the insert body 38 of the combined valve arrangement. In this position the insert body 38 can be removed, for cleaning of the valve arrangement, from the recess 16 of the housing 15. This position can be set only with the lid 10 lifted off, when the blocking slide 53 can pass, with its nose 54, through an aperture in the lid edge 11. If the lid 10 is seated on the cooker body 13, the nose 54 encounters the edge part 14 of the body 13, and the eccentric 52 is thus blocked to prevent an adjustment of the adjusting member 27 into the main position "Clean".

As is evident from Figure 1, in the main position "Clean" the venting bolt 36 is pushed inwards by means of the eccentric 31 through an aperture, not shown in more detail, of the lid edge 1-1, so that the sealing ring 12 is lifted off from the lid edge 11. At the same time the locking bolt 37 of the safety device is drawn back by the eccentric 32 into the housing 15, while the nose 54 of the blocking slide 53 protrudes from the housing 15 into the region of the outwardly-bent pot edge part 14 of the cooker body 13 and thereby prevents the lid 10 from being replaced onto the body 13 in this position of the adjusting member 27.

Figure 3 shows the safety device in the main position "Venting". In this position the common adjusting member 27 is so rotated that its eccentrics 30-32 assume the position evident from Figure 4. Through the eccentric 30 the slide 35 is shifted to the left out of the release position shown in Figure 2, so that its tines 35a and 35b protrude into the lateral slots 50 and 51 of the insert body 38 and secure the insert body 38 in its slide-in position. The cam 34 presses on the rear end region of the slide 35, so that the slide 35 assumes the oblique position evident from Figure 3. The eccentric 31 holds the venting bolt 36 still in a position in which it keeps the sealing ring 12 lifted off from the lid edge 11, whereby the steam-pressure cooker is vented.

The eccentric 32 keeps the locking bolt 37 and the eccentric 52 keeps, in accordance with Figure 10, the blocking slide 53 drawn back, so that in the position "Venting" the lid 10 can be removed from the body 13.

Figure 5 shows the safety unit in the main position "Weak" in which a weak internal pressure can form in the cooker. The common adjusting member 27 is, in this respect, so rotated that its eccentrics 30-32 assume position evident from Figure 6. This position is achieved by a rotation of the knob 28 by half a revolution relative to the main position "Clean" evident from Figure 1. In this position the slide 35 remains inserted by the eccentric 30 into the insert body 38 and retains the oblique positions evident from Figure 3 and brought about by the cam 34 of the common adjusting member 27. The venting bolt 36 is drawn back by the eccentric 31 out of the lid edge 11, so that the sealing ring 12 again butts in sealing manner against the lid edge 11 and against the body edge 14.The locking bolt 37 of the safety device is pushed out by the eccentric 32 into its locking position in which it protrudes into the region of the bent-out edge part 14 evident from Figure 1 and prevents rotation of the lid 10 and release of the bayonet union of the lid 10 from the body 13.

The compression spring 44 acting on the closure member 24 normally has a relatively small initial force so that the closure member 24, upon a slight excess pressure in the interior of the cooker, is lifted off from the valve seat 23, as is shown in Figure 5. In this position the steam forming in the interior of the cooker passes through the passage aperture 22 past the valve seat 23 and through the aperture 41 into the inner steam space 40; then partially via the steam outlet channel 19 into the open air, and partially through the connecting channel 42 into the steam passage chamber 39 and the steam outlet channel 20 to produce a signal whistle. The inner steam passage chamber 40 forms a damming chamber for the steam, which for the greater part flows away through the steam outlet aperture 19.After release of the excess pressure, the closure member 24 will again close, until once more a renrewed pressure build-up occurs in the cooker and whose strength can be read off at the indicator rod 47 protruding from the insert body 38.

Figure 6 shows the slide 35 in the main position "Weak" with its tines 35a and 35b inserted further into the slots 50, 51 of the insert body 38.

Figure 7 shows the safety unit in the main position "Strong" in which the eccentrics 3032 and 52 of the common adjusting member 27 assume the position evident from Figure 8.

In this position the cam 34 of the common adjusting member 27 so presses on the slide 35 that it is swung in an anti-clockwise direction out of its oblique position evident from Figures 3 and 5 and, in so doing, moves the insert body 38 under stronger tension of the compression spring 44 further into the recess 16. The closure member 24 is thus more strongly biassed, so that in the interior of the steam-pressure cooker a higher pressure perceptible optically at the rod 47 can build up, until opening of the closure member 24 of the combined valve arrangement occurs.Figure 7 shows the closure member 24 in the position lifted off from its valve seat 23, in which position the steam passes into the inner steam passage chamber 40 and from there flows out partially through the steam outlet channel 19 and partially via the connecting channel 42 into the outer steam passage chamber 39, forming the whistle chamber, with its steam outlet channel 20, in which respect a signal whistle is given. In the deeper slide-in position of the insert part 38, brought about by the slide 35, the steam outlet channel 19 is not masked by the transverse web 43 of the insert body 38. As the sectional views show, the lid 10 has, in front of the steam outlet channels 19 and 20, an indentation or recess in which steam condensate or possibily emerging food froth can accumulate.

In the main position "Strong" the venting bolt 36, the locking bolt 37 and the blocking slide 53 (Figure 10) maintain their position already assumed in the main position "Weak".

The lid thus remains sealed and locked.

WHAT WE CLAIM IS: 1. A steam pressure cooker comprising a body portion and a lid with a handle, the lid and body being adapted for bayonet fastening one with another, the handle having a steam pressure limiting valve, a signal whistle mechanism, and an adjusting member mounted for rotation into a plurality of operative positions, the pressure limiting valve having an insert body adapted for insertion into a recess of the lid handle and arranged to provide a displaceable abutment for a loading spring of a closure member of the valve, the insertion position of the insert body being determined by the position of a slide mounted in the lid handle, the adjusting member being operative to displace the slide and to actuate a safety device whereby the lid is either locked in position on the cooker body or a sealing ring of the cooker is displaced to vent the interior of the cooker.

2. A steam pressure cooker as claimed in Claim 1, in which the adjusting member has a plurality of adjusting cams and/or eccentncs, one of said cams or eccentrics being operative to control the position of the slide in a longitudinal displacement direction and the other being operative to control a pivot position of the slide in turn determining an insertion position of the insert body of the valve.

3. A steam-pressure cooker as claimed in Claim 1 or Claim 2, in which the slide is bifurcated at one end, engages into lateral slots on both sides of the insert body and is displaceable by means of the adjusting member into and out of engagement with the insert body.

4. A steam-pressure cooker as claimed in any preceding claim, in which the adjusting member has a cam or eccentric which cooperates with a blocking slide of the safety mechanism, the blocking slide having a nose which is able to pass through an aperture in an edge of the lid, to allow movement of the adjusting member into a main "Clean" position, only when the lid is disengaged from the cooker body.

5. A steam-pressure cooker as claimed in Claim 4 in which the safety mechanism further comprises a locking bolt and a venting bolt in addition to the blocking slide, and in which the adjusting member is mounted for rotation between the "Clean" position, in which the insert is free for removal, and three other main positions in a first of which other main positions the blocking slide is withdrawn to allow engagement between the lid and the cooker body whilst the venting bolt holds the sealing ring out of sealing engagement with the lid and cooker body, to prevent pressure build-up in the cooker body, and the slide engages the insert body, in a second of said other main positions the venting bolt is withdrawn to allow

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

edge part 14 evident from Figure 1 and prevents rotation of the lid 10 and release of the bayonet union of the lid 10 from the body 13.

The compression spring 44 acting on the closure member 24 normally has a relatively small initial force so that the closure member 24, upon a slight excess pressure in the interior of the cooker, is lifted off from the valve seat 23, as is shown in Figure 5. In this position the steam forming in the interior of the cooker passes through the passage aperture 22 past the valve seat 23 and through the aperture 41 into the inner steam space 40; then partially via the steam outlet channel 19 into the open air, and partially through the connecting channel 42 into the steam passage chamber 39 and the steam outlet channel 20 to produce a signal whistle. The inner steam passage chamber 40 forms a damming chamber for the steam, which for the greater part flows away through the steam outlet aperture 19.After release of the excess pressure, the closure member 24 will again close, until once more a renrewed pressure build-up occurs in the cooker and whose strength can be read off at the indicator rod 47 protruding from the insert body 38.

Figure 6 shows the slide 35 in the main position "Weak" with its tines 35a and 35b inserted further into the slots 50, 51 of the insert body 38.

Figure 7 shows the safety unit in the main position "Strong" in which the eccentrics 3032 and 52 of the common adjusting member 27 assume the position evident from Figure 8.

In this position the cam 34 of the common adjusting member 27 so presses on the slide 35 that it is swung in an anti-clockwise direction out of its oblique position evident from Figures 3 and 5 and, in so doing, moves the insert body 38 under stronger tension of the compression spring 44 further into the recess 16. The closure member 24 is thus more strongly biassed, so that in the interior of the steam-pressure cooker a higher pressure perceptible optically at the rod 47 can build up, until opening of the closure member 24 of the combined valve arrangement occurs.Figure 7 shows the closure member 24 in the position lifted off from its valve seat 23, in which position the steam passes into the inner steam passage chamber 40 and from there flows out partially through the steam outlet channel 19 and partially via the connecting channel 42 into the outer steam passage chamber 39, forming the whistle chamber, with its steam outlet channel 20, in which respect a signal whistle is given. In the deeper slide-in position of the insert part 38, brought about by the slide 35, the steam outlet channel 19 is not masked by the transverse web 43 of the insert body 38. As the sectional views show, the lid

10 has, in front of the steam outlet channels

19 and 20, an indentation or recess in which steam condensate or possibily emerging food froth can accumulate.

In the main position "Strong" the venting bolt 36, the locking bolt 37 and the blocking slide 53 (Figure 10) maintain their position already assumed in the main position "Weak".

The lid thus remains sealed and locked.

WHAT WE CLAIM IS: 1. A steam pressure cooker comprising a body portion and a lid with a handle, the lid and body being adapted for bayonet fastening one with another, the handle having a steam pressure limiting valve, a signal whistle mechanism, and an adjusting member mounted for rotation into a plurality of operative positions, the pressure limiting valve having an insert body adapted for insertion into a recess of the lid handle and arranged to provide a displaceable abutment for a loading spring of a closure member of the valve, the insertion position of the insert body being determined by the position of a slide mounted in the lid handle, the adjusting member being operative to displace the slide and to actuate a safety device whereby the lid is either locked in position on the cooker body or a sealing ring of the cooker is displaced to vent the interior of the cooker.
2. A steam pressure cooker as claimed in Claim 1, in which the adjusting member has a plurality of adjusting cams and/or eccentncs, one of said cams or eccentrics being operative to control the position of the slide in a longitudinal displacement direction and the other being operative to control a pivot position of the slide in turn determining an insertion position of the insert body of the valve.
3. A steam-pressure cooker as claimed in Claim 1 or Claim 2, in which the slide is bifurcated at one end, engages into lateral slots on both sides of the insert body and is displaceable by means of the adjusting member into and out of engagement with the insert body.
4. A steam-pressure cooker as claimed in any preceding claim, in which the adjusting member has a cam or eccentric which cooperates with a blocking slide of the safety mechanism, the blocking slide having a nose which is able to pass through an aperture in an edge of the lid, to allow movement of the adjusting member into a main "Clean" position, only when the lid is disengaged from the cooker body.
5. A steam-pressure cooker as claimed in Claim 4 in which the safety mechanism further comprises a locking bolt and a venting bolt in addition to the blocking slide, and in which the adjusting member is mounted for rotation between the "Clean" position, in which the insert is free for removal, and three other main positions in a first of which other main positions the blocking slide is withdrawn to allow engagement between the lid and the cooker body whilst the venting bolt holds the sealing ring out of sealing engagement with the lid and cooker body, to prevent pressure build-up in the cooker body, and the slide engages the insert body, in a second of said other main positions the venting bolt is withdrawn to allow

the sealing ring to seal the junction between cooker body and lid to allow a weak pressure build up in the cooker body with the insert body again engaged by the slide, and the locking bolt engages the cooker body to prevent disengagement of the lid from the cooker body, in a third of said other main positions the slide is in engagement with the insert body and is pivoted to displace said insert body to stress said loading spring of the valve, the venting bolt being in said withdrawn position to allow a strong pressure build up in the cooker body and said locking bolt being in said position engaging the cooker body.
6. A steam-pressure cooker as claimed in Claim 1, in which the insert body defines first and second steam passage chambers in the handle, and the chambers having respective steam outlet channels in the lid handle and being connected together by a narrow communication channel, the first steam passage chamber forming a steam damming space whose steam outlet channel is partially closed in a specific slide-in position of the insert body, and the second steam passage chamber forming a signal whistle chamber.
7. A steam-pressure cooker as claimed in Claim 1, in which in a concentric stepped passage channel of the closure member of the valve there is provided an indicator piston which is also acted upon by the internal pres sure of the cooker and which is mounted so as to be displaceable against the force of a bias spring supported by the insert body, which piston is connected to an indicator rod protruding from the insert body.
8. A steam-pressure cooker as claimed in any preceding claim, in which the portion of the lid handle bearing the valve and adjusting member is made of metal, while a hand-grip portion of the lid handle and a manually operated portion of the common adjusting member consist of a poor heat-conducting plastics material.
9. A steam-pressure cooker constructed and arranged substantially as herein described with reference to and as illustrated in the accompanying drawings.