GB1571954A - Air pump - Google Patents

Description

(54) AIR PUMP (71) We, RITE AUTOTRONICS CORPORATION, a Corporation organised and existing under the laws of the State of California, United States of America, of 3485 South La Cienega Boulevard, Los Angeles, California, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The field of this invention relates to a pump for the producing of pressurized air for the inflating of pneumatic objects, such as vehicle tires.

In the pressurizing of automobile tires and the like, there are instances when it is necessary to inflate the tire by a manual pump. The pumps that are frequently employed of this type are normally activated by a reciprocating action by either the person's hand or feet. Such prior pumps have been constructed of inferior materials in an effort to hold down manufacturing costs. Also, the assemblage techniques of such pumps have not been extremely efficient. As a result, the overall manufacturing cost is not as low as it could be and the quality of construction of such prior pumps is not at the desired level.

Frequently, the prior pumps include some type of pressure gauge to indicate to the operator the level of the pressure within the inflating device. In the past, the type of pressure gauge that has been employed has been a dial moved by a bourdon tube. This type of instrument is readily susceptible to damage and is also quite expensive to manufacture.

The air pump of this invention provides for a lever which is hingedly connected to a base. The connection between the lever and the base is simply accomplished through the use of a bushing assembly. Upon the bushing assembly is located a retainer ring assembly which is spring biased to a position to continuously maintain the pivotal interconnection between the lever and the base. An air-pressure producing actuator is pivotally connected between the lever and the free end of the base. The actuator basically comprises a conventional piston and cylinder plus a spring assembly to exert a continuous bias tending to maintain the piston rod in the extended position.

The air pump of the present invention includes a relief valve which can be preset to the desired pressure to which the object is to be inflated.

One of the primary objectives of the air pump of this invention is to construct the air pump of few parts to therefore minimize manufacturing expense.

Another objective of this invention is to construct the air pump of few parts which can be easily assembled by unskilled labor.

A further objective of this invention is that the air pump can be readily adjusted to preselected precise values of pressure prior to inflation of the inflatable object.

In accordance with the present invention there is provided an air pump for inflating an inflatable object comprising: an air pressure producing actuator comprising a cylinder containing a piston; means for moving said piston to develop pressurized air within said cylinder; and output conduit connected with said cylinder for receiving air compressed by movement of said piston and delivering said air to said object; a check valve means for said output conduit to prevent compressed air directed to said object from returning to said cylinder; a relief valve responsive to the pressure ahead of said piston and delivered to said object for selecting the value of pressure developed in said object by said actuator; and means for adjusting said relief valve for preselecting said pressure value.

The present invention will be further illustrated, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of the air pump of this invention which has been partially broken away in sections in order to observe pertinent features of this invention; Figure 2 is an enlarged view of a portion of the air pump of this invention depicting the closed position of the air pump to facilitate storage; Figure 3 is a bottom view of the hinge connection between the lever and the base of the air pump of this invention taken along line 3-3 of Figure 1; Figure 4 is a cross-sectional view taken along the line 4-4 of Figure 3; Figure 5 is a top view of the hinge connection between the actuator assembly and the base taken along the line 5-5 of Figure 1;; Figure 6 is an elevational view of the relief valve assembly incorporated within the air pump of this invention; Figure 7 is a cross-sectional view taken along line 7-7 of Figure 6; Figure 8 is a cross-sectional view similar to Figure 7 but showing the valve assembly in the initial opening position; Figure 9 is a view similar to Figure 8 but showing the valve asembly in the completely open position; Figure 10 is a cross-sectional view taken along line 10-10 of Figure 8, and Figure 11 is an exploded isometric view of the hinge connection between the lever and the base.

Referring particularly to the drawings, there is shown the air pump 100 of this invention which is composed primarily of a lever 106, a base 108 and an actuator 104.

Both the lever 106 and base 108 are constructed of a rigid material, such as aluminum. The bottom surfaces 110 and 112 of the base 108 are constructed so as to facilitate grabbing of the base 108 when it is supported upon a surface. This is to prevent undesired movement of the air pump when it is used.

The actuator 104 employs a conventional cylinder 114 within which is movably contained a piston (not shown). The piston is connected to a piston rod 116 which extends exteriorly of the cylinder 114 and is fixedly connected to a bridge plate 120.

Mounted next to the bridge plate 120 about the rod 116 is a spring retainer cap 122. A coil spring 124 is located about the piston rod 116 and is in contact with the cap 122 The opposite end of the coil spring 124 is positioned with annular groove 126 of a cap 128 which is fixedly mounted upon the cylinder 114. The coil spring 124 functions to exert a continuous bias tending to completely extend the piston rod 116 which would place the piston (not shown) in the "bottomed out" position within the cylinder 114. With the actuator assembly 104 fully compressed, the coil spring 124 is also fully compressed to the position shown in Figure 2 of the drawings. As will be explained further on in the specification, this position is the normally stowed position for the air pump of this invention since it is most compact in this position.

This position is maintained, when desired, by means of a locking clip 130. The locking clip 130 has a hook end which cooperates within an opening 132 formed within the lever 106. The locking clip 130 is pivotally mounted upon a pin 134. The pin 134 is fixedly secured between the spaced apart side members 136 and 138 of the base 108. The side members 136 and 138 are interconnected together through feet sections 110 and 112.

Located about one end of the pin 134 is a first bushing 139 with a second bushing 140 located about the other end of the pin 134. The second bushing 140 is in contact with side member 138 with the first bushing 139 in contact with the side member 136. The bridge plate 120 includes a pair of hook-shaped members 142 and 144.

Member 142 surrounds the bushing 138 slightly over one hundred and eighty degrees so as to therefore remain in position about the bushing 138. Similarly, the hook member 144 surrounds the bushing 140. The nut 146 which secures the piston rod 116 to the bridge plate 120 is positioned substantially adjacent to a bushing 148 which is rotatably mounted upon the pin 134. It is to be understood from the foregoing that the piston rod 116 is capable of pivoting movement with respect to the pin 134. This pivoting movement is necessary due to the operation of the air pump 100.

The upper end of the cylinder 114 is closed by a cover 102. Within the cover 102 is an air outlet passage 150 which is to permit air to be conducted exteriorly of the cylinder 114 to conduit 152. It is to be understood that conduit 152 will connect through an appropriate fitting to a pneumatic device, such as a tire. Within the conduit 150 is to be located a conventional one-way check valve assembly 154.

Screw threadingly received within the cover 102 is a relief valve assembly 10.

This relief valve assembly will be described in more detail further on in the specification.

The interconnection of the lever 106 to the base 108 to facilitate pivoting motion therebetween is accomplished through a segment of a cylinder 156 being integrally formed upon the lever 106. This segment of cylinder 156 is to be located upon a mating recess 158 formed within a nylon bushing 160. The bushing 160 includes an enlarged annular head 162. A pin 164 is to establish a close but movable connection within the opening 166 of the bushing 160.

The head 162 is to be located against boss 168 formed integrally upon side member 138.

With the pin 164 located within the opening 166 and the head 162 against the boss 168 and member 156 in place upon the bushing 160, a retainer ring 170 is to be placed over the member 156 and the bushing 160. This retainer ring 170 therefore forms a secure connection between the lever 106 and the side member 138 but yet permits pivoting of the lever 106 in respect fo the side member 138. A coil spring 172 is in abutting contact with the retainer ring 170. It is to be understood that a connection similar to what has previously been described in relation to the bushing 160, member 156 and pin 164 will be similarly constructed in relation to the side member 136.The free end of the spring 172 will also be in contact with retainer ring 174, therefore the spring 172 maintains the position of each of the retainer rings 170 and 174 and thereby fixes the interconnection between the lever 106 and the base 108.

Referring particularly to Figures 6-10 of the drawings, there is shown the relief valve assembly 10 incorporated in this invention which is composed primarily of an outer member or cap 12 and an inner member or body 14. The cap 12 is screw threadingly mounted upon the inner end of the body 14. The outer end of the body 14 includes a set of tapered threads 16. The threads 16 are to connect with the threaded opening 42 formed in cover 102 of pumping actuator 104.

Within the body 14 is formed an air or gas passage 18 which terminates into an air or gas receiving chamber 20. The chamber 20 in cross-section, as well as the passage 18, are circular. Movably mounted within the chamber 20 is a rubber or other slightly resilient type of valve member 22. The valve member 22 is capable of coming into flush contact with the valve seat 24 located about the inner end of the passage 18 and thereupon close the passage 18 and prevent air from passing from the passage 18 into the chamber 20. Surrounding member 22 is an outer valve member 23. Members 22 and 23 are located in a close fitting relationship but permitting movement therebetween.

Also movably mounted within the chamber 20 and in a continuously abutting contact with the valve member 22 and member 23 is a first spring retainer 26. A portion of the retainer 26 surrounds a portion of the member 23 in a close-fitting relationship but permitting movement therebetween. The retainer 26 will normally be constructed of a rigid material, such as plastic. A coil spring 28 extends within the chamber 20 and connects with the spring retainer 26.

The free end of the coil spring 28 is located about a second spring retainer 30.

The second spring retainer 30 fits within appropriate recess 32 formed within a plug 34. The plug 34 is screw threaded in the outer end of the cap 12.

The end of the cap 12 located directly adjacent the body 14 is formed into a beveled surface 36. Upon the beveled surface 36 are located a first indicia in the form of the numerals zero, five, ten and fifteen, each of the numerals being located ninety degrees apart. Also formed on the exterior surface of the cap 12 adjacent the beveled surface 36 are a plurality of graduations in the form of lines 38. It is to be noted that there are twenty in number of the lines 38 and the construction of the assembly 10 is such that if the cap 12 is rotated the distance of one graduation line to the next graduation line, it will be required to have five additional pounds per square inch of air presure to unseat the valve member 22.

Also located upon the exterior surface of the body 14 is a second indicia in the form of a series of numerals and lines. The second indicia is divided into graduations of ten pounds per square inch of pressure (although the last digit, the zero has been omitted). As the cap 12 is screwed upon the body 14 and the forward surface of the cap 12 moves a total distance of one graduation to another graduation, that an additional pressure of ten pounds per square inch is required within the passage 18 in order to unseat the valve member 22.

To acquire divisions of pressure of less than ten pounds per square inch, it is necessary to observe the indicia 38 which is in graduations of one pound per square inch. Therefore, the operator of the device 10 of this invention can, by rotating of the cap 12 with respect to the body 14, preselect the operating pressure of the device of this invention to within five pounds per square inch increments, from values of five pounds per square inch to one hundred and twenty pounds per square inch.

Upon the gas pressure within the passage 18 exceeding the preselected pressure level for the member 22, the member 22, as well as the spring retainer 26, is moved initially within the chamber 20 to the position shown in Figure 8 of the drawings. In this position, the pressurized gas within the passage 18, as well as in the forward portion of the chamber 22, is permitted to come into contact with the outer valve member 23 since a substantially increased area is exposed to the pressurized gas (entire forward surface of member 22 plus forward surface of member 23 as opposed to only the top of member 22), the members 22 and 23 now move with a "snap". As a result, pressurized gas is permitted to be quickly expelled to the ambient through the relief passage 40.

If the pressure within the passage 18 falls just slightly below the preselected pressure, the member 22 will again be reseated against the valve seat 24 thereby closing passage 18. Also, the outer valve member 23 will be reseated in contact with the portion of body 14 surrounding the passage 18. In this position, the tip of member 23 slightly deforms (or crushes) producing a leakage free seal. The pressure level established within the inflatable device (not shown) will be maintained at the desired level.

WHAT WE CLAIM IS: 1. An air pump for inflating an inflatable object comprising: an air pressure producing actuator comprising a cylinder containing a piston; means for moving said piston to develop pressurized air within said cylinder; an output conduit connected with said cylinder for receiving air compressed by movement of said piston and delivering said air to said object; a check valve means for said output conduit to prevent compressed air directed to said object from returning to said cylinder; a relief valve responsive to the pressure ahead of said piston and delivered to said object for selecting the value of pressure developed in said object by said actuator; and means for adjusting said relief valve for preselecting said pressure value.

2. An air pump as claimed in claim 1 wherein; said relief valve comprises an air passage connected with said cylinder to be responsive to the air pressure received by said output conduit; a valve seat at the end of said air passage; a valve member located adjacent said seat; a spring means for normally biasing said valve member against said seat to seal said passage, and an ambient relief passage connected with said air passage upon movement of said valve member from said seat by air pressure in said air passage.

3. An air pump as claimed in claim 2 wherein; support means for mounting said valve member and for providing an enlarged area subject to said air pressure after movement of said valve member away from said seat are provided.

4. An air pump as claimed in claim 3 wherein; said adjusting means comprising means for adjusting the amount of biasing of said spring means against said valve member.

5. An air pump for inflating an inflatable object, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   20 to the position shown in Figure 8 of the drawings. In this position, the pressurized gas within the passage 18, as well as in the forward portion of the chamber 22, is permitted to come into contact with the outer valve member 23 since a substantially increased area is exposed to the pressurized gas (entire forward surface of member 22 plus forward surface of member 23 as opposed to only the top of member 22), the members 22 and 23 now move with a "snap". As a result, pressurized gas is permitted to be quickly expelled to the ambient through the relief passage 40.

   If the pressure within the passage 18 falls just slightly below the preselected pressure, the member 22 will again be reseated against the valve seat 24 thereby closing passage 18. Also, the outer valve member 23 will be reseated in contact with the portion of body 14 surrounding the passage 18. In this position, the tip of member 23 slightly deforms (or crushes) producing a leakage free seal. The pressure level established within the inflatable device (not shown) will be maintained at the desired level.

   WHAT WE CLAIM IS: 1. An air pump for inflating an inflatable object comprising: an air pressure producing actuator comprising a cylinder containing a piston; means for moving said piston to develop pressurized air within said cylinder; an output conduit connected with said cylinder for receiving air compressed by movement of said piston and delivering said air to said object; a check valve means for said output conduit to prevent compressed air directed to said object from returning to said cylinder; a relief valve responsive to the pressure ahead of said piston and delivered to said object for selecting the value of pressure developed in said object by said actuator; and means for adjusting said relief valve for preselecting said pressure value.
2. 2. An air pump as claimed in claim 1 wherein; said relief valve comprises an air passage connected with said cylinder to be responsive to the air pressure received by said output conduit; a valve seat at the end of said air passage; a valve member located adjacent said seat; a spring means for normally biasing said valve member against said seat to seal said passage, and an ambient relief passage connected with said air passage upon movement of said valve member from said seat by air pressure in said air passage.
3. 3. An air pump as claimed in claim 2 wherein; support means for mounting said valve member and for providing an enlarged area subject to said air pressure after movement of said valve member away from said seat are provided.
4. 4. An air pump as claimed in claim 3 wherein; said adjusting means comprising means for adjusting the amount of biasing of said spring means against said valve member.
5. 5. An air pump for inflating an inflatable object, substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.