Patent GB-455965-A (GB)
Title: Improvements in and relating to pumps, syringes, and like appliances for surgical and other purposes
IPC: A61M3/00
Filed: 1935-04-27
Abstract: 455,965. Syringes and pumps. SCHULZ, H. H., 39, Westbourne Park Road, Paddington, and A. G. PRODUCTS, Ltd., Carlton Bridge, Great Western Road, both in London. April 27, 1935, Nos. 12611 and 19381. [Class 102 (i)] [See also Groups VI and XXIX] A vaginal or other syringe comprises a cylinder 30 of rigid material such as synthetic resin having surrounding the sides and end thereof a rubber envelope 37, which expands as a reservoir on filling the syringe with liquid and contracts to inject the liquid when released. The cylinder 30 is formed with a screw-threaded internal flange 32 which receives a screw plug 33 having a valve seating 33a. The base of the envelope 37 is preferably concave and is' thickened as at 40 and formed integrally with a rubber valve 41 engaging the seating 33a. The cylinder 30 is formed with ports 35, adjacent to ports 36 in the plug 33, and also with ports 26 controlled by a rubber ring valve 48a. An internal flange 40a on the envelope is gripped between a flange on the plug 33 and the end of the cylinder 30. In use injection liquid forced from a tap or by pumping action past the valve 48a expands the envelope 37 and is retained until released past the valve 41 by finger pressure on the part 40. The upper part of the cylinder 30 may contain a piston comprising a rubber plug 43 moulded on to a sleeve 39 and connected to a nozzle 45. The piston is returned after the instroke by a rubber sleeve 42 integral with plug 43 and passing between the parts 39, 45. The sleeve 42 is turned over the edge of cylinder 30, and this sleeve and the envelope 37 have beaded edges engaging recesses between flanges on the cylinder 30 and are held in position by a screw-threaded cap 50. The nozzle 45 has telescopically housed within it an extension nozzle 44 securable to it in an angular position by engagement of a screw thread 24b with an obliquely set screw thread 24a. The part 44 has a screw-threaded nozzle head 48 containing a terminal soft rubber plug 47 formed with a central channel 47a and lateral channels 47b. To fill the envelope 37 the nozzle 47 is pressed against the base of a liquid-container and the piston reciprocated. Downward pressure closes the channels 47a, 47b the plug 47 thereby acting as a non-return valve. Alternatively the nozzle 48 may be temporarily replaced by a fitting for filling from the tap, the piston and associated parts being preferably removed and the part 45 combined with cap 50. When out of use the appliance of Fig. 2 is enclosed in an external casing 46. The channel 47a may be enlarged to receive the tubular shank of a tapered nozzle, which is screwed into a contracted portion of the tube 44. In modifications of the piston construction the sleeve 39 may have at its lower end an inturned and upturned flange screw threaded to receive the part 45, a bead on the sleeve 42 being clamped between the parts ; alternatively a rubber plug integral with sleeve 42 and surrounding and above the upturned portion of sleeve 39 may be moulded about a ring in screw-threaded engagement with the upturned portion and the nozzle 45. In a modified syringe a tubular guide for the piston is secured to the plug 33 and the valve 41 is replaced by a plug seating on the end of the guide within the piston and connected to the part 40 by a valve stem. The nozzle-tip valve 47 is replaced by a tip of ordinary construction and the piston modified to provide through channels controlled by a rubber disc suction valve covering the working face. The valve 48a is replaced by a ring of circular section. In a further modification of Fig. 2, the cylinder 30 has an integral or attached end plate replacing the parts below the valve 48a and apertured to receive a valve such as 41 detached from the envelope 37. The envelope has a domed end resting on the valve and is secured to the end plate by an external ring. The first Provisional Specification refers to the construction, wherein the discharge valve is within the piston and connected to the envelope by a stem, as having flap valves, or an elastic ring valve on the piston and states that'the discharge valve may be replaced by an elastic ring valve covering parts in the cylinder wall and opened by the arms of a spider expanded by pressure on the end of the envelope. This Specification also refers to the envelope as formed with screw rings at each end screwed on to an external screw thread in the cylinder, the rings being connected by rigid members if desired. Specification 449,259 is referred to.