A SLIDING TAP VALVE

Abstract: A tap handle or knob (1) for the valve spindle of a tap valve intended for liquid-carrying conduits, the handle being constructed so as to prevent excessive tightening of the valve spindle. The handle (1) includes a handle-part (2) and a spindle connector (3) having located therebetween a sliding clutch (9, 10) which disengages when the handle-part (2) is overtightened. The sliding clutch comprises two mutually opposing, circular toothed surfaces (9, 10), of which one is incorporated in the tap-part (2) and the other in the spindle connector (3), and further comprises an elastic force generator (4) operative in resiliently urging the surfaces (9, 10) together.

Description: A sliding tap valve The present invention relates to a tap handle for turning the valve spindle of a tap valve fitted to a liquid-con¬ ducting conduit, preferably a tap valve for domestic water-pipes. Tap valves, faucet valves and like valves intended for liquid-carrying conduits, and in particular for domestic water-pipes, are often provided with a resilient sealing means, known generally as a sealing washer, which is urged against a valve seat when closing the valve. The sealing washer is usually placed on a valve plug, or valve stem, or integrated therewith, the valve plug or valve stem being actuated with the aid of a rotatable spindle, which in turn is actuated by a handle or knob. The handle is normally a one-piece structure firmly mounted on the valve spindle and held against co-rotation therewith, wherewith each turn of the handle results in corresponding rotation of the valve spindle about its long axis, which in turn • results in displacement of the valve plug and therewith the sealing washer or like means. When a sealing washer is new, it is sufficient to press the washer very lightly against the valve seal in order to stop the flow of liquid through the tap. It is normal, however, for the majority of users to turn the handle and therewith the valve spindle, to an unnecessary extent which results in excessive spindle travel and excessive compression of the washer, resulting in unnecessary rapid wear on the washer. In addition, this excessive rotation of the handle/spindle is frequently accompanied with wear on the valve seat, which often needs to be beamed as a result thereof. Consequently, there is a need for a valve arrangement which prevents unnecessary rotation of the handle, and therewith resultant unnecessary compression of the sealing washer. The present invention solves the aforesaid problem in a 5 tap or faucet construction which comprises a handle-part and a spindle connector, and which is characterized by a slipping clutch arranged between the handle-part and the spindle connector. When the handle-part is turned and tightened to an unnecessary extent, the handle-part beco- 10 mes disengaged from the spindle connector, therewith pre¬ venting subsequent excessive tightening of the valve spindle and excessive compression of the sealing washer. - The invention will now be described in more detail with 15 reference to an exemplifying embodiment of the invention illustrated in the acocompanying drawing, in which Fig. 1 is a longitudinal sectional view of the construc¬ tion according to the invention; 20 Fig. 2 is a plan view of the circular, toothed surfaces; and Fig. 3 is a cross-sectional view of the teeth illustrated 25. in Fig. 2, taken on the line III-III in Fig. 2. As shςwn in Fig. 1, the handle or knob 1 incorporates a handle-part 2, a spindle connector 3 and a coil spring 4. 30 The handle-part 2 comprises an internally tubular part 5 which is closed at its upper end by a cover plate 6. Located on the inner surface of the tubular part 5 is a shoulder 7, which extends around the full circumference of 5 said part. The shoulder 7 has formed therein a recess 8 which accommodates the spring 4. The inwardly facing sur¬ face of the cover plate 6 presents a circular, toothed surface 9, which will be described in more detail herein¬ after. The centre axis of the cylindrical spindle connector 3 located in the handle-part 2 is common with the centre axis of the handle-part 2. Located on the top of the spindle connector 3 is a circular toothed surface 10, the' form and function of which will be described hereinafter. As will be seen from Fig. 1, the end of the spindle con¬ nector remote from the toothed surface 10 engages around a valve spindle of a tap valve fitted to a liquid-carrying conduit or pipe. The valve spindle, not shown, is in acti¬ vating connection with a valve plug or valve stem intended for sealing engagement with a valve seat. The cylindrical spindle connector 3 has provided at the top thereof a plate 11, the upper surface of which forms the toothed surface 10. The spring 4 accommodated in the recess 8 acts against the plate 11 in a manner to press the toothed surfaces 9 and 10 together. The configuration of the toothed surfaces 9 and 10 is illustrated in Figs. 2 and 3- The teeth are arranged in the form of a fan, and in profile are triangular in shape with planar flanks 12,13. The flanks 12 and 13 of respective teeth are inclined at mutually different angles, with the one flank angle in the tap closing direction being less than 90° and the other flank angle in the tap opening direction being 90 or more. In most cases the arrangement will function satisfactorily even when the angle g is less than 90°, although excessive force may cause the teeth to disengage or move out of mesh. Consequently, in order to guard against this, the angle β is made at least 90°. The angle may also vary, although it should not be smaller than 15° or greater than 80°. . As illustrated in Fig. 1, the surfaces 9 and 10 are pres¬ sed together. Since the two surfaces are mirror images of one another, the tooth flanks 12 on the surface 10 will lie against corresponding tooth flanks 12 on the surface 9, while the tooth flanks 13 on the surface 10 lie against corresponding tooth flanks 13 on the surface 9. When the tap handle is turned normally in the tap closing direction, the tooth flanks 12 are in abutment with one another and rotary movement of the handle-part 2 is trans¬ mitted through the flanks 12 to the spindle connector 3, which in turn transmits said movement to the spindle (not shown), which then presses the valve plug or valve stem sealingly against a valve seat. When this seal is accom¬ plished, the spindle connector resists further rotation. As a result, the tooth flanks 12 slide against one ano- ther, while compressing the coil spring 8, such as to mutually disengage or "unmesh". By varying the angle at which the teeth are inclined and the strength of the coil spring, it is possible to arrange for such "unmeshing" of the teeth to take place at different degrees of torque, this torque being dependent on the pressure at which the washer or like seal is required to tighten against the valve seat. For example, when the washer and the valve plug or valve stem have the form of a one-piece plastic unit, the washer or like seal need only be pressed lightly against the valve seat. Although such valve plugs have earlier been available on the market, the use of the plugs has been forbidden due to the fact that they fracture when the handle is tightened excessively. The construction according to the invention enables such valve taps to be used without risk in this regard. The use of soft and resilient sealing washers or like seals has * a protective effect on the valve seat, i.e. causes less strain to be exerted thereon, thereby considerably lengthening the use¬ ful life of the taps to which they are fitted. The spindle connector is turned solely to the extent required to ob¬ tain an effective seal between the valve seat and the val¬ ve plug or valve stem, irrespective of the number of turns made on the handle-part 2. When the handle-part 2 is turned in the valve opening direction, the tooth flanks 13 lie against one another and rotational movement of the handle-part 2 is transmitted to the spindle connector 3 through the tooth flanks 13. When these flanks are inclined at an angle of 90° or there- above, the handle-part 2 is unable to disengage from the connector 3. As will be understood, the illustrated coil spring can be replaced with some other suitable elastic device capable of resiliently urging the surfaces 9 and 10 towards one another, for example as elastic polymeric material, an hydraulically operating device or the like. The illustrated embodiment is not restrictive of the invention, but can be modified within the scope of the following claims.

Claims: CLAIMS 1. A tap handle for the valve spindle of a tap valve intended for liquid-carrying conduits, comprising a handle-part and a spindle connector, characterized by a sliding clutch (9,10) arranged between the handle-part (2) and the spindle connector (3). 2. A tap handle according to Claim 1, characterized in that the sliding clutch comprises two circular, toothed and mutually opposed surfaces (9,10) which have mutually common centre axes, the one firmly fixed in the handle- part (2) and the other on the spindle connector (3)., said toothed surfaces being pressed against one another by a resilient elastic device (4). 3. A tap handle according to Claim 1 or 2, characterized in that in the closing direction of the valve the teeth on respective surfaces (9,10) have an angle α of less than 90 , while in the opening direction of the valve the angle β of respective teeth is approximately 90 or more. 4. A tap handle according to any of the preceding Claims, characterized in that the tooth angle α is between 15 and 80°. 5. A tap handle according to any of the preceding Claims, characterized in that the resilient device (4) is a coil spring. 6. A tap handle according to any of the preceding Claims, characterized in that the resilient device (4) consists of an elastic plastics material.

Inventors: JOHANSSON ALLAN, LILJEKVIST BORIS, JOHANSSON, ALLAN, LILJEKVIST, BORIS
Applicants: JOHANSSON ALLAN, LILJEKVIST BORIS, JOHANSSON, ALLAN, LILJEKVIST, BORIS
Application year: 1986
Main classification: F16K31
IPC codes: F16K31