EP0136000A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Paper-forming machine
Assignee: Beloit Walmsley Ltd
•
Filing: 1984-07-18
•
Granted: —
•
Expires: 2004-07-18
Abstract
Abstract In a twin wire paper forming machine an endless top wire (14) passes round a lead-in roll (12) and meets a bottom wire (15) in the region of a lead-in-foil cover (1). The two wires pass over a secondary foil cover (4) which presents alternately solid and open areas to create pulsating pressure on stock between the wires, and then below a secondary trailing cover (10) whose leading edge doctors water on the top wire into an autoslice (9), and the top wire (14) is separated from the bottom wire (15) in the region of a sheet transfer box (11) to pass round a drive roll (13) and return to the lead-in roll. The leading edge of the transverse bars (41) or blades of the secondary foil cover (4) doctor water off the bottom wire. The secondary foil cover (4) and the secondary trailing cover (10) establish successively sharper downwardly forwardly and upwardly forwardly convex paths for the wires which promote dewatering. A primary trailing cover (8) and a primary autoslice (7) can additionally be disposed above the top wire between the lead-in-foil cover (1) and the secondary foil cover (4). The lead-in-foil cover and the secondary foil cover can form parts of a composite adjustably mounted unitary structure.
Inventors
- 👤 Ronnie Abraham Arav
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 09:36
CPC Classifications
D; D21; D21F; D21F9/00; D21F9/003; D21F3/00; D21F1/00; D21F1/48
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
152 words
A twin wire paper forming machine in which a bottom wire passes.over a lead-in-foil and over a sheet transfer box downstream therefrom, and an endless top wire which turns over a lead-in-roll and meets the bottom wire in the region of the lead-in-foil cover and is separated from the bottom wire in the region of the sheet transfer box to pass over a drive roll and return to the lead-in roll, characterised in that the bottom wire (15) passes over a secondary foil cover (4) which is disposed downstream of the lead-in-foil cover (1) and has alternately solid and open bottom wire engaging areas, and the top wire (14) passes below a trailing cover (10) which is disposed downstream of the secondary foil cover (4) and has a continuous top wire engaging surface of which the leading edge (101) serves to doctor water on the top wire into a secondary autoslice (9).
Claim 2
Dependent Claim
152 words
A twin wire paper forming machine in which a bottom wire passes.over a lead-in-foil and over a sheet transfer box downstream therefrom, and an endless top wire which turns over a lead-in-roll and meets the bottom wire in the region of the lead-in-foil cover and is separated from the bottom wire in the region of the sheet transfer box to pass over a drive roll and return to the lead-in roll, characterised in that the bottom wire (15) passes over a secondary foil cover (4) which is disposed downstream of the lead-in-foil cover (1) and has alternately solid and open bottom wire engaging areas, and the top wire (14) passes below a trailing cover (10) which is disposed downstream of the secondary foil cover (4) and has a continuous top wire engaging surface of which the leading edge (101) serves to doctor water on the top wire into a secondary autoslice (9).
Claim 3
Dependent Claim
46 words
A twin wire paper forming machine as claimed in claim 1, characterized in that.the secondary foil cover (4) comprises a series of foils (41) extending transversely across the path of the wires (14,15) and spaced from one another in the direction of movement of the wires.
Claim 4
Dependent Claim
47 words
A twin wire paper forming machine as claimed in claim 1, characterised in that the secondary foil cover (4) comprises a series of blades (42) extending transversely across the path of the wires (14,15) and spaced from one another in the direction of movement of the wires.
Claim 5
Dependent Claim
50 words
A twin wire paper forming machine as claimed in claim 3, characterized in that each of the blades (42) is inclined at an acute angle to the direction of movement of the wires such that its leading edge can doctor water off the under surface of the bottom wire (15).
Claim 6
Dependent Claim
32 words
A twin wire paper forming machine as claimed in any of claims 1 to 4, characterised by means for creating a vacuum in a box (5) below the secondary foil cover (4).
Claim 7
Dependent Claim
44 words
A twin wire paper forming machine as claimed in any of claims 1 to 5, characterised by means for creating a vacuum in a secondary chamber or saveall (91) above the top wire ('14) and with which the secondary autoslice (9) is in communication.
Claim 8
Dependent Claim
37 words
A twin wire paper forming machine as claimed in any of claims 1 to 6, characterised in that the secondary trailing cover (10) is blank and presents a continuous wire engaging surface to the top wire (14).
Claim 9
Dependent Claim
48 words
A twin wire paper forming machine as claimed in any of claims 1 to 7, characterised in that the secondary foil cover (4) establishes a downwardly forwardly convex path for the wires (14,15) and the secondary trailing cover (10) establishes an upwardly forwardly.convex path for the wires (14,15).
Claim 10
Dependent Claim
41 words
9: A twin wire paper forming machine as claimed in claim 8, characterised in that the radius of curvature of the convex path established by the secondary trailing cover (10) is smaller than that -established by the secondary foil cover (4).
Claim 11
Dependent Claim
54 words
A twin wire paper forming machine as claimed in claim 2 and in any of claims 5 to 9, characterised in that a further primary trailing cover (8) and an .associated primary autoslice (7) are disposed above the top wire (14) downstream of the lead-in-foil (1) and upstream of the secondary foil cover (4).
Claim 12
Dependent Claim
41 words
A twin wire paper forming machine as claimed in claim 10, characterised by means for creating a vacuum in a primary autoslice chamber or saveall (71) above the top wire (14) and with which the primary autoslice (7) is in communication.
Claim 13
Dependent Claim
35 words
A twin wire paper forming machine as claimed in claim 10 or 11, characterised in that the primary trailing cover (8) is blank and presents a continuous wire engaging surface to the top wire (14).
Claim 14
Dependent Claim
24 words
A twin wire paper forming machine as claimed in any preceding claim, characterised in that the lead-in-foil cover has a curved wire engaging surface.
Claim 15
Dependent Claim
32 words
A twin wire paper forming machine as claimed in claim 13, characterised in that the lead-in-foil cover (1) is blank and presents a continuous wire engaging surface to the bottom wire (15).
Claim 16
Dependent Claim
40 words
A twin wire paper forming machine as claimed in claim 13, characterised in that the lead-in-foil cover (1) has a slotted cover, and means are provided for creating a vacuum in a lead-in-foil box (2) below the lead-in-foil cover (1).
Claim 17
Dependent Claim
49 words
A twin wire paper forming machine as claimed in claim 3 or 4, or.in claim 3 and in-any of claims 5 to 15, characterised in that the lead-in-foil cover (1) and the secondary foil cover (4) form part of a composite unitary structure (30) which is adjustably mounted (31,32).
Claim 18
Dependent Claim
32 words
A twin wire paper forming machine as claimed in any preceding claim, characterised by interchangeable means (93) for varying the width and/or shape of the inlet opening of the secondary autoslice (9).
Claim 19
Dependent Claim
22 words
A twin wire paper forming machine as claimed in any preceding claim, characterised in that the secondary trailing cover (10) is interchangeable.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.