Patent GB-190313237-A (GB)
Title: Improvements in Milking Apparatus.
Inventor: LAWRENCE WILLIAM HENRY
Filed: 1903-06-13
Granted: 1904-06-02
Abstract: 13,237. Lawrence, W. H., and Kennedy, R. June 13. Cow-milkers.-Three methods of milking cows and other animals by means of special apparatus of the type described in Specifications Nos. 6129 and 14,619, A.D. 1896, No. 8846, A.D. 1897, No. 21,738, A.D. 1898, and No. 23,353, A.D. 1901, are described. In the first method, pulsations of vacuum or pneumatic pressure are effected in the outer chambers of double-chambered teat cups and the degree of vacuum in the inner chambers is regulated, while air is admitted intermittently to the milk conductor to assist the flow of milk. A pulsator similar to that described in Specification No. 23,353, A.D. 1901, is mounted on a base, which serves as a cover for the milk receptacle and is arranged with ports and passages leading from the valve seating of the pulsator to the vacuum pipe, the atmosphere, the milk receptacle, and the teat cups of one or more animals. The vacuum in the milk receptacle is regulated by means of an adjustable spring-controlled reducing-valve. A doubleseated screw valve is provided so that air may be drawn into the apparatus from the receptacle or from the atmosphere. The milk passes through special vertical inspection devices, and air is admitted behind it through a spring-controlled valve in the double claw, the movements of the valve synchronizing with those of the pulsator. When the air supplied to the outer chambers is taken direct from the atmosphere, this valve establishes communication between a restricted opening in the milk conductor and an opening in the air conductor, the head of the valve forming a piston working in a chamber but provided with clearance or passages so that a limited amount of air may pass. When the air supply is taken from the milk receptacle, the valve is modified in form and admits air from the atmosphere. In the second method of milking, pulsations of vacuum or pneumatic pressure are produced in both the inner and outer chambers of the teat cups, either simultaneously or alternately according to whether both walls of the teat cups are flexible or only the inner one. This is accomplished by means of a modification of the apparatus described in Specification No. 23,353, A.D. 1901. The piston of the pulsator is caused to operate a similar piston by means of a pendulum lever, so that pulsations are produced in two sets of ports and passages. The claw used may be of the form shown in Fig. 22. The milk conductor 47 and air conductor 48 are provided with four branches 33, 32 respectively, and the milk conductor 47 with a special double spring-controlled valve. When the vacuum in the conductor 47 is near its maximum, the small valve 59 opens and air is drawn in through the aperture 63, which may be provided with means for regulating its area, until the vacuum is so reduced that the valve closes. The larger valve 61 is open to the atmosphere and acts as a piston in the chamber 62. One pulsating piston may be used instead of two, and the apparatus may be used in connection with single-chambered teat cups, two cups in each set of four being connected so that the contraction of one pair takes place simultaneously with the expansion of the other. In the third method of milking, variations of vacuum or pneumatic pressure are effected in the outer chambers of the teat cups and the vacuum is periodically partially or entirely cut off from the inner chambers in synchronism with the variations in the outer. This is preferably done by means of a modification of the differential pulsating piston or valve described in Specification No. 6129, A.D. 1896. Fig. 10 shows the apparatus in section. In the position shown, the vacuum has access from the milk receptacle by the passage 70, valve cavity 69, port 71, and pipe 72 to the teat cups, and also from the teat cups by way of the valve in the claw, the pipe 78, port 77, and passage 75 to both ends of the cylinder 68. When the combined force, due to the vacuum and to the pressure of the air on the small ends 65, is sufficiently great to overcome the adjustable pull of the spring 80, the piston 67 moves inwards and opens the port 83<a>, thus admitting air to the annular area 66. This forces the piston against the adjustable stop 79 and partially or completely closes the ports 70, 71, thus cutting off the vacuum from the teat cups. In this position, the cups are in communication with the atmosphere through the ports 83<a>, 77, and the vacuum falls till the spring 80 moves the piston back. The outer end of the piston is surrounded by a flanged leather 73 held against it by an endless spiral spring or elastic ring 74. The passage 75 is furnished with a regulator screw or valve 76. In claws for use with single-chambered teat cups, the milk conductor forms a continuation of the air conductor and no valve is used. In a modified form, this differential device may be made to actuate the pulsator described in relation to the first method of milking. In this form, the piston at the junction of the smaller and larger parts forms a valve which closes against a seat. It is provided with cavities and passages, which alternately connect each end of the pulsator cylinder with the vacuum and the air supply. The air for reducing the vacuum in the teat cups is obtained from the valve chamber by means of a pipe, a blind port, and a restricted passage. The areas of the passages in the valve casing are regulated by screws. Fig. 6 shows a special form of inspection device, in which the transparent portion 110 is held vertical by a screw cap 114 and surrounds a hollow stem 111, up the outside of which the milk rises till it reaches the apertures 113, when it flows out through the duplex stop-cock 117. A small hole 112 constitutes a byepass, through which all the milk passes when the quantity falls below a certain amount. In another arrangement, the glass cylinder 110 is surrounded by a spiral spring or by a metal case having apertures, and the milk flows over the top of the stem 111. In another arrangement, vertical inspection glasses are fitted below the cooks 117 and are jammed up tight by screw nozzles. Fig. 25 shows a teat cup having both walls 122, 123 flexible and a cup end or junction 127 with a nozzle 25 and a screwed end 128 coned to receive the lower end of the inner wall which is held between it and the conical end of a nozzle 124 forced upwards by a screw cap 130. Other forms of cups with rigid outer casing and modified means of connecting it to the inner flexible lining are described. The lining may be grooved and graduated in thickness, and may be stretched by means of a screwed nozzle in which is a small aperture leading from the inner to the outer chamber. In one form, the lower end of the lining is moulded to fit elastically over a bead on a nozzle and the outer casing is shaped to correspond. In another form, a plain lining is employed, the lower end being drawn through a sleeve and waist on the outer case and expanded and secured by a cone sliding on a nozzle and forced upwards by a nut. The Provisional Specification states that the pulsations in the outer chambers of the teat cups may be produced by connecting them with the passage leading from the valve to the cylinder end of the mechanism described in Specification No. 23,353, A.D. 1901. It also states that the inner lining of teat cups with flexible outer casings squeezes the milk from the teat by its own resiliency, which may be increased by means of springs or elastic material, and that the claw may be constructed with one body piece divided into two compartments communicating with the inner and outer chambers of the teat cups.