Valve block

Abstract: A valve block for a glass container forming machine comprises a frame (2) supporting a plurality of valve stations (3). Each of the stations (3) is provided with a valve (20). The frame (2) comprises pressure passages (12,14) connected to supplies of compressed air, and control sleeves (38,40) at each station (3) determine which supply (12,14) is available to the valve (20) at that station. The valves (20) and the control sleeves (38,40) are all accessible from one face (4) of the valve block.

Description: This invention relates to valve blocks. Conventional glassware forming machines of the I.S. or individual section type comprise a plurality of sections, mechanically similar, operating out of phase with each other to produce a continuous stream of glass containers. Each section comprises a number of pneumatically operated mechanisms and each such mechanism comprises one or more pneumatic valves to control its operating sequence. Such pneumatic valves are normally controlled by solenoid operated pilot valves, which solenoid operated valves are controlled by a computerised control system for the machine. Conveniently the pneumatic valves and the associated solenoid operated pilot valves for a single section are mounted in an array in a valve block which is mounted on the section, and significant constraints are placed upon the design of such valve blocks by the need to accommodate it in the space available in the width of one section and also by the need to make it reasonably accessible for repair and adjustment. A typical valve block is shown in US 3 918 489. This valve block comprises two castings secured together, one casting supporting the solenoid operated pilot valves in an array comprising two lines of such valves, and the other casting supporting the pneumatic valves associated with the pilot valves. To gain access to the pneumatic valves, for repair or adjustment, it is necessary to separate the two castings, which is a very time consuming operation. Another valve block is shown in US-A-4,382,451. This block comprises a frame having a plurality of control valves at valve stations in two rows on opposite faces of the block. Provided in the valve block is an exhaust passage, a first, low pressure, passage and a second, high pressure, passage, which passages all extend lengthwise through all the valve stations. The control valves of one of these rows of valve stations are connected to the low pressure passage. Each valve station of the other row of valve stations comprises an inlet passage which extends across the two pressure passages and a control sleeve in the inlet passage which connects a selected one only of the pressure passages to the control valve at the valve station. The valve block of US-A-4,382,451 thus comprises one face which supports one row of control valves, and a third face which allows access to the control sleeves. Such an arrangement is expensive to manufacture because of the number of cross drillings which are needed, and inconvenient to maintain and adjust because access is needed to all faces of the valve block. The geometry of the block also means that only two rows of control valves, one on each of the opposed faces, can be provided. Further, it is desirable in a valve block to provide throttle valves which control the flow of air, firstly from the supply of air to the control valve, and secondly from the control valve to exhaust. Access to such throttle valves for convenient adjustment is also desirable. Again, such access is not provided in US-A-4,382,451. The present invention is directed to a valve block generally of the type disclosed in US-A-4,382,451 as defined in the preamble of claim 1. It is an object of the present invention to provide a valve block which is economical in construction and in which access to component parts for repair or modification is facilitated. According to the present invention there is provided a valve block as defined in the characterising clause of claim 1. There now follows a description, to be read with reference to the accompanying drawings, of a valve block embodying the invention. In the accompanying drawings, Figure 1 shows a perspective view, with some parts removed, of a valve block embodying the invention; Figure 2 shows a view of a section taken along the line II-II of Figure 1; Figures 3 and 4 show control sleeves; and Figure 5 shows a view similar to Figure 2 but comprising a different arrangement of control sleeves. The valve block (Figure 1) comprises a frame 2 which provides a plurality, namely 26, of valve stations 3 arranged in one or more, in fact in two, rows. The frame 2 is rectangular in shape and has a front face 4 and a rear face 6, which provide a front face and a rear face for each valve station. Figures 2 and 5 each show a transverse section through two valve stations. The frame 2 comprises, extending lengthwise through the frame, two exhaust passages 8 and 10, a first, high, pressure passage 12 and a second, low, pressure passage 14. The exhaust passages 8 and 10 are each associated with the valve stations in separate rows; viewing Figure 2 the passage 8 extends lengthwise through all the valve stations in the upper row of valve stations, the passage 10 through all the valve stations in the lower row. The passages 12 and 14 each extend through both rows of valve stations. The lower valve station 3 shown in Figure 2 will now be described: it will be understood that the construction of each valve station 3 in the lower row is the same so far as the frame 2 is concerned, while the construction of each valve station 3 in the upper row is effectively the same as those in the lower row, being mirror images. The precise configuration of parts associated with the frame at each valve station may differ, as will be explained later. The lower valve station 3 comprises an inlet passage 16 which extends directly from the rear face 6 to the front face 4 across the two pressure passages 12 and 14. A supply passage 18 also extends from the rear face 6 to the front face 4 of the station. Associated with the valve station 3 is a pilot air operated control valve 20 which comprises connecting air passages namely an inlet 22, a supply outlet 24 and an exhaust outlet 26. The valve 20 is mounted on the front face 4. The inlet 22 mates with a valve inlet passage 28 of the frame 2, the supply outlet 24 with the supply passage 18, and the exhaust outlet 26 with a valve exhaust passage 30 of the frame 2. The valve inlet passage 28 leads from the face 4 to a chamber 32 which is open to the inlet passage 16. The valve exhaust passage 30 leads from the face 4 to a chamber 34 which opens through an orifice 36 into the exhaust passage 10. The valve station 3 also comprises a control sleeve in the inlet passage 16 which determines whether the valve inlet passage 28 is connected to the high pressure passage 12 or the low pressure passage 14. In Figure 2, the lower valve station 3 has a control sleeve 38 which connects the valve inlet passage 28 of that station to the high pressure passage 12, while the upper valve station 3 has a control sleeve 40 which connects the valve inlet passage 28 of that station to the lower pressure passage 14. The sleeve 38, which may be termed a high pressure sleeve, is shown in Figure 3. It is tubular in form and comprises a closed end 42 from which extends a cylindrical wall 44 to an open end 50. Four radially spaced entry ports 46 are provided in the wall 44 close to the closed end 42. Similar ports 48 are provided adjacent the open end 50 of the wall 44; the end 50 provides an annular end face 52. The sleeve 40, which may be termed a low pressure sleeve, is shown in Figure 4. It resembles the sleeve 38 being tubular in form, and comprises a thick closed end 54 from which a cylindrical wall 56 extends to an open end 62. Radially spaced entry ports 58 are provided in the wall 56, adjacent the closed end 54 and similar entry ports 60 are provided adjacent the open end 62 of the wall 56 which provides an annular end face 64. The control sleeves are held in position in the frame 2 by stud arrangements 66 mounted on the front face 4 of the valve station 3, (best seen in Figure 5) which stud arrangements also provide throttle valves. Each stud arrangement 66 comprises a sleeve 68 comprising a narrower portion 70 and a larger portion 72. The larger portion 72 is provided with a screw thread which extends to a faceted head 74, and the larger portion 72 is screwed into an appropriate screw threaded bore in the front face 4 of the frame 2. A valve member 76 is mounted in the sleeve 68 and comprises a head 78, having a chamfered seating face 80, and mounted for sliding movement in the larger portion 72 of the sleeve 68, and a stem 82 which comprises a threaded portion 84 which engages in an internally threaded portion 86 of the narrower portion 70 of the sleeve 68. The valve members can thus be adjusted in the sleeve 68 by rotation of the members 76, achieved through use of a square head 88. As can be seen from Figure 2, the stud arrangement 66 may be used in one of three contexts. Viewing the lower most stud arrangement 66 shown in Figure 2, this serves to provide a throttle valve for controlling the passage of air from the chamber 34 through the orifice 36 into the exhaust passage 10. The chamfered face 80 is arranged opposite the orifice 36, and can be brought close to the orifice to restrict the flow of air from the exhaust outlet 26 of the valve 20 through the chamber 34 to exhaust, if required, by adjustment of the face 80 by rotation of the valve member 76. The next lowest stud arrangement viewing Figure 2 is associated with a high pressure control sleeve 38. The sleeve 68 of the stud arrangement is screwed into the frame 2 and the end face of the larger portion 72 of the sleeve 68 engages the annular end face 52 of the sleeve 38 to hold the sleeve in place in the inlet passage 16. The head 78 of the valve member 76 is dimensioned to be slidable within the cylindrical wall 44, and thus by adjustment of the position of the valve member 76, specifically of the axial position of the head 78 with respect to the entry ports 48, it is possible to control the rate of flow of air from the high pressure passage 12, through the control sleeve 38 in the inlet passage 16 and out through the ports 48 into the chamber 32. The next lowest stud arrangement viewing Figure 2 is associated with a low pressure control sleeve 40, and it can be seen that adjustment of the position of the valve member 76 will control the flow of low pressure air from the low pressure passage 14 through the entry ports 58, through the wall 56 of the control sleeve 40 and out through the ports 60 into a chamber equivalent to the chamber 32. The stud arrangements 66 also provide for the accurate location of the valves 20 at each valve station. Each valve 20 is provided with two through bores 90, 92 each provided with enlarged end portions 100,102,104,106. The valve 20 is positioned at a valve station by being positioned on two adjacent stud arrangements 66, extending through the bores 90 and 92. The enlarged portions 100 and 102 fit over the faceted heads 74 of the sleeve 68, the bores 90,92 closely surround the sleeves 68, and the enlarged portions 104, 106 accommodate nuts 108 which are secured on threaded end portions of the sleeves 68 to hold the valve 20 firmly in position. Each valve 20 is a pilot operated valve controlled by a solenoid operated pilot valve 110. It can be seen that the valve block just described is highly adaptable and convenient of access. Each valve station 3 can be arranged to control high pressure air, by use of a sleeve 38 or low pressure air, by use of a sleeve 40. If, for example for [Plunger up operating air,] air at a pressure different from that of the main high pressure or low pressure air is required, such air may be provided to the valve block through a dedicated passage 112 (see Figure 5) and conveyed to the valve at the valve station through a simple sleeve 114 which does not connect to either the high pressure passage 12 or the low pressure passage 14. Thus each valve station may be modified, by variation of the control sleeves, or repaired, by replacement of the valve 20, with access only to one face of the valve block. Further, the stud arrangements 66 allow both the incoming air from the supply and the air passing to the exhaust from the valve 20 to be throttled; this throttling of air passing to exhaust allows conventional check valves to be dispensed with.

Claims: A valve block comprising: a frame (2) which provides a plurality of valve stations (3) arranged in one or more rows, an exhaust passage (8, 10), a first pressure passage (12) and a second pressure passage (14) all extending lengthwise through all the valve stations in one row, a control valve (20) associated with each valve station, each valve station (3) comprising an inlet passage (16) extending across the two pressure passages (12, 14), and a control sleeve (38, 40) in the inlet passage (16) which connects a selected one only of the pressure passages (12, 14) to an inlet (22) of the control valve (20), characterised in that : the frame has a front face (4) and a rear face (6) which provides a front face (4) and a rear face (6) of each valve station, the inlet passage (16) of each valve station extending from the rear face (6) to the front face (4) of the station, and a supply passage (18) of each valve station extending from the rear face (6) to the front face (4) of the station, the frame has a passage (32) extending between an inlet opening (28) on the front face (4) of the station and the inlet passage (16), and a passage extending between an exhaust opening (30) on the front face of the station and the exhaust passage (8, 10), and the valve block comprises, at each station (3), a first throttle valve for controlling the passage of air to the valve (20) from the inlet passage (16) of the frame, and a second throttle valve for controlling the passage of air from the valve (20) to the exhaust passage (8, 10) of the frame, the two valves extending from the front face (4) of the station, and in that the control valve (20) associated with the station is mounted on the throttle valves and has inlet (22), exhaust (26) and supply (24) passages communicating respectively with the inlet opening (28), exhaust opening (30) and supply passages (18) of the frame. A valve block according to claim 1, wherein the second throttle valve comprises a control face (80) which can be adjusted with respect to an inlet orifice (36) in the wall of the exhaust passage (8, 10), thus to provide a throttle valve. A valve block according to one of claim 1 and 2, wherein the first throttle valve is provided by a first stud arrangement (66) mounted on the front face (4) of the station. A valve block according to claim 3, wherein the first stud arrangement extends into the inlet passage (16) to hold the control sleeve (38, 40) in position. A valve block according to claim 4, wherein the first stud arrangement comprises a head (78) which cooperates with the control sleeve (38, 40) to provide a throttle valve. A valve block according to claim 3, wherein the second throttle valve is provided by a second stud arrangement (66) mounted on the front face (4) of the station and the control valve (20) is mounted on the two stud arrangements. A valve block according to any one of the preceding claims, in which the valve stations are arranged in two rows. A valve block according to claim 7, wherein the two pressure passages (12, 14) extend through the valve stations in both rows.

Inventors: MEYER WILLI, MEYER, WILLI
Applicants: EMHART GLASS SA, EMHART GLASS S.A.
Application year: 1998
Main classification: F15B13
IPC codes: C03B9, F15B11, F15B13