Abstract: A vehicle differential gear includes first and second pinion gears rotatably supported by a differential case; first and second side gears meshing with the first and second pinion gears and each coupled to corresponding one of a pair of output shafts; and a center washer, a first end washer and a second end washer each having a sliding surface that slides with an axial end face of at least one side gear of the first or second side gears, the sliding surface being lubricated by a lubricating oil; wherein a surface treatment for enhancing a solid lubricating property is performed on the washers.

Abstract: A vehicle differential gear includes first and second pinion gears rotatably supported by a differential case; first and second side gears meshing with the first and second pinion gears and each coupled to corresponding one of a pair of output shafts; and a center washer, a first end washer and a second end washer each having a sliding surface that slides with an axial end face of at least one side gear of the first or second side gears, the sliding surface being lubricated by a lubricating oil; wherein a surface treatment for enhancing a solid lubricating property is performed on the washers.

Abstract: At the time for forming an internal gear from a raw material 2 of an internal gear, first, the raw material 2 is externally inserted onto a forming die 3 and fixed to the forming die 3 through a pressing die 4. Next, a forming roll 5 is moved in a direction as indicated by an arrow B of FIG. 6 while rotating the forming die 3. By this, the inner peripheral surface of the raw material 3 is pressed against an outer gear part 3b formed on the outer peripheral surface of the forming die 3 so that an internal gear part 1c is formed on the inner peripheral surface of the raw material 2. The rotating direction of the forming die 3 is selected such that the first end part of the outer gear part 3b located on the front side in the feeding direction of the forming roll 5 is moved ahead in the rotating direction (the direction as indicated by an arrow A of FIG. 6) of the second end part located on the rear side in the feeding direction of the forming roll 5.

Abstract: At the time for forming an internal gear from a raw material 2 of an internal gear, first, the raw material 2 is externally inserted onto a forming die 3 and fixed to the forming die 3 through a pressing die 4. Next, a forming roll 5 is moved in a direction as indicated by an arrow B of FIG. 6 while rotating the forming die 3. By this, the inner peripheral surface of the raw material 3 is pressed against an outer gear part 3b formed on the outer peripheral surface of the forming die 3 so that an internal gear part 1c is formed on the inner peripheral surface of the raw material 2. The rotating direction of the forming die 3 is selected such that the first end part of the outer gear part 3b located on the front side in the feeding direction of the forming roll 5 is moved ahead in the rotating direction (the direction as indicated by an arrow A of FIG. 6) of the second end part located on the rear side in the feeding direction of the forming roll 5.

Abstract: A receiving portion 2e for rotatably receiving therein a planetary gear 3, is formed between a plurality of retaining protrusions 2d of a carrier. A connection portion 2f extending annularly about a rotation axis L is formed on an outer peripheral of a distal end portion of each retaining protrusion 2d. Through this connection portion 2f, the distal end portions of the respective retaining protrusions 2d are connected to each other. Owing to this arrangement, each retaining protrusion 2d is reinforced to minimize its deformation. As a result, deformation of the receiving portion 2e is greatly reduced and the planetary gear 3 receiving in the receiving portion 2e can rotate smoothly.

Abstract: A receiving portion 2e for rotatably receiving therein a planetary gear 3, is formed between a plurality of retaining protrusions 2d of a carrier. A connection portion 2f extending annularly about a rotation axis L is formed on an outer peripheral of a distal end portion of each retaining protrusion 2d. Through this connection portion 2f, the distal end portions of the respective retaining protrusions 2d are connected to each other. Owing to this arrangement, each retaining protrusion 2d is reinforced to minimize its deformation. As a result, deformation of the receiving portion 2e is greatly reduced and the planetary gear 3 receiving in the receiving portion 2e can rotate smoothly.

Abstract: The plunger pump according to the present invention discharges fuel by reciprocation of a plunger, and comprises metallic diaphragm type dampers, provided at a fuel inlet side and a fuel outlet side, respectively, for reducing pressure pulsation of fuel. Each metallic diaphragm type damper comprises a pressure chamber for receiving fuel pressure, a back pressure chamber into which gas is charged, and a metallic diaphragm for defining the pressure chamber and the back pressure chamber. Since the metallic diaphragm type dampers are provided at the fuel inlet side and the fuel outlet side, respectively, noise and vibration caused by pressure pulsation are reduced at the fuel inlet side and the fuel outlet side. Also, since the diaphragms are metallic diaphragms, deterioration thereof generated by fuel liquid and back pressure gas is low, reliability is high, and the lifetime is long.

Abstract: A diaphragm type damper has a combined member, which is formed by welding a marginal portion of a diaphragm to a half body having a concave portion formed therein, and is fixed to a pressure chamber portion to which high pressure fluid is introduced. A wall thickness of a welding portion of the half body is not relevant to welding, and the heat capacity of the welding portion is small. Since the half body is allowed to have a large wall thickness, leakage from the welding portion and damage to that portion can be prevented. In addition, the diaphragm type damper of this present invention can be easily assembled, since it requires only fixing the combined member to the pressure chamber portion.

Abstract: A communication path (32) for communicating a hermetically closed space (S) with an inlet port (20) is formed within a casing (1). An oil reservoir (30) having an inside capacity much greater than an inside capacity of the communication path (32) is formed in an intermediate part of the communication path (32).

Abstract: An externally threaded portion 31 of a valve body 10 is threadingly engaged with an internally threaded portion Hb formed on the opening portion side of an attachment hole Ha. A flange portion 32 of the valve body 10 is brought into abutment with an upper surface Hc of the housing H, so that the valve body 10 is fixed to the housing H. A lower end of the valve body 10 is located away from a bottom surface of the attachment hole Ha. A valve seat 23 and a guide hole 24 are formed inside the valve body 10. The valve seat 23 and the guide hole 24 are located on a lower side than the externally threaded portion 31. A valve element 50 is provided inside the valve body 10. This valve element 50 includes a seat portion 51 rest on the valve seat 23, and a guide portion 55 slidably engageable with the guide hole 24. A lower end opening portion of the guide hole 24 is shielded with a shielding plate 25. An orifice 25a is formed in the shielding plate 25.